IMPROVING THE DECISION MAKING PROCESS OF DEMOLITION … Thi Bui Thesis.pdf · improving the decision-making process of demolition waste management in urban redevelopment projects

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam i

IMPROVING THE DECISION-MAKING

PROCESS OF DEMOLITION WASTE

MANAGEMENT IN URBAN

REDEVELOPMENT PROJECTS

IN VIETNAM

Diep Thi BUI

Master of Science

Dr. Timothy Rose

Prof. Martin Skitmore

Submitted in fulfilment of the requirements for the degree of

Doctor of Philosophy

School of Civil Engineering and Built Environment

Science and Engineering Faculty

Queensland University of Technology

2018

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam

Keywords

Decision-making framework

Decision support system

Demolition waste

Framework for demolition waste management

GIS-based model

Supporting database

Urban redevelopment

Urban renewal

Waste management

Vietnam

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam iii

Abstract

Over the last three decades, rising population and increasing urbanisation have

significantly impacted on aging urban infrastructure in developed and developing

countries. Thus, sustainable urban redevelopment has become an important strategy in

many cities around the world. Although urban redevelopment benefits communities

by upgrading housing conditions and infrastructure, it can be a source of conflict

resulting from the imbalance among economic, environmental and social objectives.

A particularly significant problem is the massive waste stream that is produced as a

result of the demolition process of aging buildings in urban redevelopment projects.

Effectively planning for demolition waste management practice, therefore, has become

a priority for policy makers. In Vietnam, urban redevelopment projects are now

required to be delivered in a sustainable way due to the rising awareness of sustainable

construction processes. However, the management of demolition waste has not been

effective yet due to the confusion of how a sustainability policy is implemented in

practice and the insufficient knowledge and the lack of information available to

project’s stakeholders on demolition waste management. Within this context, this

research develops a decision-making framework consisting of key decision-making

factors and a database to support the decision-making process of demolition waste

management in Vietnamese urban redevelopment projects.

Firstly, this research develops a preliminary conceptual framework that encapsulates

19 themes under five categories including technical, environmental, economic, social,

and institutional factors. This framework forms 53 factors in total that are regarded as

important influencing elements in demolition waste management decision-making

process. Twenty-four critical factors were then identified through a questionnaire

survey of 216 stakeholders in Vietnamese urban redevelopment projects, allowing the

revision and refinement of the conceptual framework. Twenty-two semi-structured

interviews were then conducted with a focus on the in-depth understanding of the

importance of each critical factor and the development of action plans aiming at

improving demolition waste management decision-making process in Vietnam.

Further, a GIS-based data model is proposed as a decision support tool for demolition

waste management at district level. This model is designed for the case study in


Vietnam in which spatial information of urban redevelopment projects and information

of demolition waste management are integrated. Finally, a meaningful decision-

making framework is proposed for improving demolition waste management in

Vietnamese urban redevelopment projects.

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam v

Table of Contents

Keywords ................................................................................................................................. ii

Abstract ................................................................................................................................... iii

Table of Contents ...................................................................................................................... v

List of Figures ......................................................................................................................... xi

List of Tables ........................................................................................................................ xiii

List of Abbreviations .............................................................................................................. xv

Statement of Original Authorship ......................................................................................... xvi

Acknowledgements .............................................................................................................. xvii

Chapter 1: Introduction ...................................................................................... 1

1.1 INTRODUCTION .......................................................................................................... 1

1.2 RESEARCH BACKGROUND ...................................................................................... 1

1.3 RESEARCH PROBLEM................................................................................................ 3

1.4 RESEARCH QUESTIONS ............................................................................................ 4

1.5 RESEARCH AIM AND OBJECTIVES ........................................................................ 5

1.6 RESEARCH SIGNIFICANCE ....................................................................................... 6

1.7 OVERVIEW OF RESEARCH METHODOLOGY ....................................................... 7

1.8 SCOPE AND LIMITATIONS OF THE RESEARCH ................................................... 9

1.9 OUTLINE OF THE THESIS .......................................................................................... 9

1.10 SUMMARY .................................................................................................................. 11

Chapter 2: Literature Review ........................................................................... 12

2.1 INTRODUCTION ........................................................................................................ 12

2.2 URBAN REDEVELOPMENT ..................................................................................... 12

2.2.1 Definitions .......................................................................................................... 12

2.2.2 Global trend in urban redevelopment ................................................................. 15

2.3 THE LINK BETWEEN URBAN REDEVELOPMENT AND SUSTAINABILITY .. 20

2.4 DEMOLITION WASTE MANAGEMENT ................................................................. 23


2.4.1 The lifecycle of the built environment ............................................................... 23

2.4.2 Integrated approach to waste management in construction industry ................. 25

2.4.3 Current status of demolition waste .................................................................... 28

2.5 DEMOLITION WASTE MANAGEMENT IN URBAN REDEVELOPMENT

PROJECTS ............................................................................................................................. 32

2.5.1 Overview of demolition waste in urban redevelopment projects ...................... 32

2.5.2 Current research trend in urban redevelopment demolition waste

management ....................................................................................................... 34

2.6 URBAN REDEVELOPMENT DEMOLITION WASTE MANAGEMENT IN

VIETNAM ............................................................................................................................. 41

2.6.1 Urban redevelopment in Vietnam ...................................................................... 41

2.6.2 Demolition waste management in Vietnamese urban redevelopment

projects ............................................................................................................... 45

2.7 RESEARCH GAP ........................................................................................................ 48

2.8 RESEARCH CONCEPTUAL FRAMEWORK .......................................................... 50

2.8.1 Organisational decision-making ........................................................................ 50

2.8.2 Research factors influencing demolition waste management in urban

redevelopment projects ...................................................................................... 53

2.9 SUMMARY ................................................................................................................. 62

Chapter 3: Research Design .............................................................................. 63

3.1 INTRODUCTION ....................................................................................................... 63

3.2 RESEARCH PROPOSITION ...................................................................................... 63

3.3 RESEARCH PHILOSOPHY ....................................................................................... 64

3.4 RESEARCH DESIGN ................................................................................................. 67

3.4.1 Research approach ............................................................................................. 67

3.4.2 Selection of research methods ........................................................................... 69

3.5 RESEARCH PROCESS .............................................................................................. 71

3.5.1 Establishing conceptual framework ................................................................... 71

3.5.2 Development of the framework ......................................................................... 71

3.5.3 Development of supporting database ................................................................. 73

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam vii

3.6 RESEARCH METHODS ............................................................................................. 73

3.6.1 Literature review ................................................................................................ 73

3.6.2 Questionnaire survey .......................................................................................... 75

3.6.3 Interview ............................................................................................................. 79

3.6.4 Case study........................................................................................................... 81

3.7 ETHICAL CONSIDERATIONs .................................................................................. 83

3.8 SUMMARY .................................................................................................................. 84

Chapter 4: Survey Study ................................................................................... 85

4.1 INTRODUCTION ........................................................................................................ 85

4.2 QUESTIONNAIRE DESIGN ...................................................................................... 85

4.3 SURVEY INSTRUMENT............................................................................................ 87

4.4 SURVEY RESPONSE RATE AND VALIDITY ........................................................ 88

4.5 QUESTIONNAIRE RESULTS AND ANALYSES .................................................... 89

4.5.1 Respondents’ profiles ......................................................................................... 89

4.5.2 Reliability of the questionnaire .......................................................................... 92

4.5.3 Respondents’ perspectives ................................................................................. 92

4.5.4 Comparison of rankings among five groups of respondents .............................. 98

4.5.5 Critical decision-making factors for demolition waste management in

Vietnamese urban redevelopment projects ....................................................... 103

4.5.6 Agreement on critical decision-making factors ................................................ 107

4.6 MAIN FINDINGS OF THE QUESTIONNAIRE SURVEY ..................................... 117

4.6.1 Main findings ................................................................................................... 117

4.6.2 Revised conceptual framework ........................................................................ 118

4.7 SUMMARY ................................................................................................................ 119

Chapter 5: Interview ........................................................................................ 121

5.1 INTRODUCTION ...................................................................................................... 121

5.2 INTERVIEWEES’ SELECTION AND THEIR BACKGROUND ........................... 121

5.2.1 Selection of interviewees .................................................................................. 121

5.2.2 Interviewee background ................................................................................... 122


5.3 INTERVIEW INSTRUMENTS................................................................................. 124

5.4 INTERVIEW FORMAT AND STRUCTURE .......................................................... 124

5.5 INTERVIEW RESULTS AND DISCUSSION ......................................................... 126

5.5.1 Choosing demolition methods ......................................................................... 126

5.5.2 Demolition waste management procedures ..................................................... 127

5.5.3 Waste classification and estimation ................................................................. 128

5.5.4 Planning for landfill, sorting area, and storage ................................................ 129

5.5.5 Training ............................................................................................................ 131

5.5.6 Stakeholder awareness ..................................................................................... 132

5.5.7 The uniqueness of demolition waste ................................................................ 133

5.5.8 “3R” strategies and recovery ........................................................................... 134

5.5.9 Environmental impact assessment ................................................................... 135

5.5.10 Cost estimation and cost-effectiveness .......................................................... 136

5.5.11 Preservation .................................................................................................... 137

5.5.12 Reduction of disturbance on the community .................................................. 138

5.5.13 Regulations/guidelines ................................................................................... 139

5.5.14 Stakeholder engagement ................................................................................ 139

5.5.15 Information and communication .................................................................... 140

5.6 IMPROVING DEMOLITION WASTE MANAGEMENT IN VIETNAMESE

URBAN REDEVELOPMENT PROJECTS ........................................................................ 141

5.7 SUMMARY ............................................................................................................... 144

Chapter 6: Case study ...................................................................................... 145

6.1 INTRODUCTION ..................................................................................................... 145

6.2 CASE STUDY PURPOSE ......................................................................................... 145

6.3 case STUDY SITE CONTEXT ................................................................................. 146

6.4 case study DATA COLLECTION METHOD ........................................................... 149

6.4.1 The spatial data ................................................................................................ 150

6.4.2 The attribute information ................................................................................. 153

6.5 DEVELOPMENT OF DEMOLITION WASTE DATABASE ................................. 153

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam ix

6.6 CASE STUDY RESULTS AND DISCUSSION ....................................................... 154

6.6.1 Demolition waste estimation ............................................................................ 154

6.6.2 Demolition waste classification ........................................................................ 158

6.6.3 Demolition waste transport .............................................................................. 160

6.6.4 Selection of landfill sites .................................................................................. 162

6.7 SUMMARY ................................................................................................................ 164

Chapter 7: Discussion and Findings ............................................................... 165

7.1 INTRODUCTION ...................................................................................................... 165

7.2 CONCEPTUAL FRAMEWORK ............................................................................... 165

7.3 REVISED CONCEPTUAL FRAMEWORK ............................................................. 167

7.3.1 Technical factors .............................................................................................. 168

7.3.2 Environmental factors ...................................................................................... 171

7.3.3 Economic factors .............................................................................................. 173

7.3.4 Social factors .................................................................................................... 173

7.3.5 Institutional factors ........................................................................................... 174

7.4 GIS-BASED DECISION SUPPORT SYSTEM ......................................................... 176

7.5 FINALISED DECISION-MAKING FRAMEWORK ............................................... 178

7.6 FINDINGS RELATED TO THE EXTANT LITERATURE ..................................... 181

7.7 SUMMARY ................................................................................................................ 182

Chapter 8: Conclusion ..................................................................................... 183

8.1 INTRODUCTION ...................................................................................................... 183

8.2 REVIEW OF RESEARCH OBJECTIVES AND DEVELOPMENT PROCESSES . 183

8.3 DECISION-MAKING FRAMEWORK FOR IMPROVING DEMOLITION WASTE

MANAGEMENT IN VIETNAMESE URBAN REDEVELOPMENT PROJECTS ........... 185

8.3.1 The factors influencing demolition waste management in Vietnamese

urban redevelopment projects........................................................................... 185

8.3.2 Action plans for improving demolition waste management in Vietnamese

urban redevelopment projects........................................................................... 188

8.3.3 Supporting database for urban redevelopment demolition waste

management decision-making process ............................................................. 191


8.4 RESEARCH CONTRIBUTIONS .............................................................................. 192

8.4.1 Contribution to academic knowledge .............................................................. 193

8.4.2 Contribution to the industry practice ............................................................... 194

8.5 RESEARCH LIMITATIONS .................................................................................... 195

8.6 RECOMMENDATIONS FOR FUTURE RESEARCH ............................................ 196

Bibliography ........................................................................................................... 199

Appendices .............................................................................................................. 219

Appendix A. Questionnaire survey ...................................................................................... 219

Appendix B. Survey Analysis results ................................................................................... 233

Appendix C. Invitation letter – Interview............................................................................. 251

Appendix D. Data collection and analysis for case study .................................................... 253

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam xi

List of Figures

Figure 1-1: Research focus ......................................................................................... 3

Figure 2-1: Triple bottom line of sustainable urban redevelopment ......................... 22

Figure 2-2: A C&D waste management framework. ................................................ 24

Figure 2-3: Environmental effects as a function of time. ......................................... 25

Figure 2-4: Conceptual model for sustainable construction waste management

(Manowong, 2012) ....................................................................................... 26

Figure 2-5: System for integrated demolition waste management ........................... 27

Figure 2-6: Hierarchy of construction and demolition waste management

(Peng, Scorpio, & Kibert, 1997) .................................................................. 28

Figure 2-7: The aging blocks in Ba Dinh district, Hanoi .......................................... 42

Figure 2-8: The aging buildings in District 10, Ho Chi Minh City .......................... 43

Figure 2-9: Aging building in Le Chan district, Hai Phong ..................................... 44

Figure 2-10: Steps of a sustainable decision-making model for waste

management. ................................................................................................ 52

Figure 2-11: Conceptual framework of effective DW management in urban

redevelopment projects ................................................................................ 56

Figure 3-1: Research proposition .............................................................................. 64

Figure 3-2: Philosophical Positions (Creswell, 2013) .............................................. 65

Figure 3-3: Research process .................................................................................... 72

Figure 3-4: Process of GIS-based model for the development of supporting

database ........................................................................................................ 83

Figure 4-1: Distribution of the respondents by the places in which they

implemented the urban redevelopment projects .......................................... 91

Figure 4-2: Revised conceptual framework for improving decision-making in

DW management for urban redevelopment projects ................................. 119

Figure 6-1: Location of Ba Dinh district ................................................................. 148


Figure 6-2: Locations of four urban redevelopment projects in Ba Dinh district ... 152

Figure 6-3: The total volume of DW generation in four urban redevelopment

projects ....................................................................................................... 156

Figure 6-4: The DW volume generation in four projects presented in GIS

model .......................................................................................................... 157

Figure 6-5: Demolition waste generation divided by materials in four urban

redevelopment projects .............................................................................. 158

Figure 6-6: Demolition waste generation divided by materials in four urban

redevelopment projects presented in GIS model ....................................... 159

Figure 6-7: Estimation of the number of pick-up trucks per project for non-

inert waste .................................................................................................. 161

Figure 6-8: The information of C&D waste landfill sites in Hanoi ........................ 163

Figure 7-1: Finalised decision-making framework for improving DW

management in urban redevelopment projects at district level .................. 180

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam xiii

List of Tables

Table 1-1: Research methods are used to address the research objectives ................. 8

Table 2-1: Key reviewed themes ............................................................................... 34

Table 2-2: Research factors influencing DW management in urban

redevelopment project .................................................................................. 55

Table 3-1: Quantitative, qualitative, and mixed methods approach analyses by

Creswell (2009) ............................................................................................ 69

Table 3-2: Summary of selection of research methods ............................................. 70

Table 3-3: Methods of statistical analysis ................................................................. 76

Table 4-1: Structure of the questionnaire .................................................................. 87

Table 4-2: Respondents’ information ........................................................................ 90

Table 4-3: Academics’ ratings of decision-making factors of demolition waste

management ................................................................................................. 93

Table 4-4: Planners’ ratings of decision-making factors of demolition waste

management ................................................................................................. 94

Table 4-5: Consultants’ ratings of decision-making factors of demolition waste

management ................................................................................................. 95

Table 4-6: Engineers’ rating of decision-making factors of demolition waste

management ................................................................................................. 97

Table 4-7: Policy Makers’ rating of decision-making factors of demolition

waste management ....................................................................................... 98

Table 4-8: A comparison of ratings of decision-making factors for urban

redevelopment DW management among key stakeholders ....................... 100

Table 4-9: Factors rated by the respondents as important and very important

(mean >4) ................................................................................................... 104

Table 4-10: Kendall’s coefficient of concordance .................................................. 106

Table 4-11: Comparison of rating of critical decision-making factors for

improving urban redevelopment DW management among key

stakeholders ................................................................................................ 109


Table 4-12: One-Way ANOVA statistic for log-transformed data of critical

decision-making factors for improving urban redevelopment DW

management ............................................................................................... 111

Table 4-13: Adjusted differences based on p-value generated in Kruskal-

Wallis test ................................................................................................... 112

Table 4-14: Probability values in Mann-Whitney test on three critical factors ...... 114

Table 4-15: Probability values in 2-sample t test on three critical factors .............. 115

Table 4-16: Adjusted differences based on p-value generated in Mann-

Whitney test ............................................................................................... 116

Table 5-1: Statistical Breakdown of Interviewees .................................................. 122

Table 5-2: Interviewee Profiles ............................................................................... 123

Table 5-3: Interview questions ................................................................................ 125

Table 5-4: Major findings of the interview study .................................................... 141

Table 6-1: The project information of the case study ............................................. 149

Table 8-1: The research design related to research objectives ................................ 184

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam xv

List of Abbreviations

ArcGIS GIS software made by ESRI

DW Demolition waste

C&D Construction and demolition

GIS Geographic Information System

MSWM Municipal solid waste management

SPSS Statistical Package for the Social Sciences

FDR False Discovery Rate


Statement of Original Authorship

The work contained in this thesis has not been previously submitted to meet

requirements for an award at this or any other higher education institution. To the best

of my knowledge and belief, the thesis contains no material previously published or

written by another person except where due reference is made.

Signature: QUT Verified Signature

Date: November 2018

improving the decision-making process of demolition waste management in urban redevelopment projects in vietnam xvii

Acknowledgements

I am close to accomplishing the greatest challenge of my life thus far. This journey has

been accompanied by unforgettably sweet and bitter moments. I would like to take this

opportunity to thank those whose support, assistance, and favour have been stepping

stones in completing my PhD journey.

First and foremost, I would like to express my sincerest appreciation to my previous

principal supervisor, Professor Jay Yang, who originally suggested and guided the

research in the first milestone of my PhD study. My deepest appreciation goes to my

current principal supervisor, Dr. Timothy Rose, who has always been actively engaged

throughout my PhD project. There is no way I could have completed this thesis without

extensive support from my principal supervisor. Special thanks are also extended to

Professor Martin Skitmore, my associate supervisor, who supported and shared

knowledge and experience in data analysis. Thank you, my supervisory team; you have

kindly opened up the doors and guided me to academia.

I gratefully acknowledge the School of Civil Engineering and Built Environment,

Science and Engineering Faculty, Queensland University and Technology (QUT) and

Institute of Strategy and Policy on Natural resources and Environment (ISPONRE) in

Vietnam for supporting me in the PhD journey. My special thanks go to Ms. Sascha

Mitchell, a fantastic English teacher in the EAP course sponsored by QUT, who helped

me in improving my academic writing skills. I also acknowledge the services of

professional editor, Diane Kolomeitz, who provided copyediting and proofreading

services, according to the guidelines laid out in the university-endorsed national

‘Guidelines for editing research theses’.

My love and deep gratitude go to my parents and my parents-in-law, who have always

provided me with their unconditional love, encourage and support throughout my PhD

journey and my academic career. My enduring appreciation and deep love are due to

my husband, Bich, my son, Khai, and my daughter, Phuong, who understand,

spiritually support and are the source of my motivation, whether my mood is up or

down. This dissertation would not have been possible without you; I give you all my

love.


Last but not least, many thanks to my sisters and brothers, and my dearest friends in

Vietnam, at QUT, and in Brisbane who are always beside me, encouraging and

inspiring me to overcome the challenges in my life.

Chapter 1: Introduction 1

Chapter 1: Introduction

1.1 INTRODUCTION

This chapter discusses the research background and the research problem statement of

the study. Research questions, research objectives, and research methodology are

formulated to achieve the research aims and figure out the significance of the research.

This is followed by a discussion on the scope and limitations of the research. The final

section of the chapter provides the outline of the thesis and the summary of the study.

1.2 RESEARCH BACKGROUND

Throughout the last century, rapid population growth and increasing urbanisation have

had a profound influence on urban infrastructure. Urban redevelopment has become

inevitable in the process of urban change, which is one of the important concerns in

both theory and practice. Large-scale housing and urban redevelopment activities are

taking place in many cities all over the world, in order to upgrade housing conditions

and urban infrastructure. Urban redevelopment is considered a complex issue because

of the large number of stakeholders, the financial commitment needed, and the impact

on society and the environment (Roussat, Dujet, & Mehu, 2009b; Zheng, Shen, &

Wang, 2014). More recently, urban redevelopment issues have become the focus of

attention in both developed and developing countries, resulting in several studies on

pertinent topics (Couch & Dennemann, 2000; Munoth, Jain, Raheja, & Brar, 2013;

Yau & Ling Chan, 2008). Researchers have been paying increasing attention to

sustainable urban redevelopment to balance the economic, social and environmental

issues resulting from redevelopment processes (Leigh & Patterson, 2006; Munoth, et

al., 2013; Yau & Ling Chan, 2008; Zheng, et al., 2014). According to Zheng et al.

(2014), despite the benefits of a holistic perspective of urban sustainable

redevelopment, most researchers in this discipline have concentrated exclusively on

such aspects as heritage conservation, housing development and resident relocation,

while other urban redevelopment issues, such as demolition waste and resource

management, also need to be taken into consideration (Fang & Zhang, 2003; Yeoh &

Huang, 1996).

2 Chapter 1: Introduction

Despite the increase in global research into construction waste management (Yuan &

Shen, 2011), demolition waste (DW) management has received little attention,

particularly from an urban redevelopment perspective at both project and regional

levels (Yuan, Shen, & Wang, 2011). To date, critical reviews of construction and

demolition (C&D) waste management research have been conducted by Wu, Yu, Shen

and Liu (2014) and Yuan & Shen (2011). However, while such reviews provide a

broader coverage of C&D waste management in the construction industry, they do not

focus specifically on DW management, especially in the field of urban redevelopment.

Many countries, such as Hong Kong, the USA, and the UK, have associated with the

problems of DW with urban redevelopment (Couch & Dennemann, 2000; Farfel et al.,

2005; Poon, Ann, & Ng, 2001). For example, due to the rapid of urban redevelopment,

Hong Kong is facing the threat of overflowing landfills (Poon, Yu, See, & Cheung,

2004). It is estimated that about 1.8 million US housing units were demolished in the

2000s (Farfel, et al., 2005) that resulted in a massive amount of DW. However, for

developing countries in particular, the issue of urban redevelopment DW management

has received less attention from both the academic community and practitioners.

Vietnam has also encountered the issues of urban redevelopment. Many cities in

Vietnam have experienced decades of exponential population growth and

urbanisation. In addition, the demand for improving the quality of urban life has been

conducive to the redevelopment of many old parts of cities. In fact, Vietnam urban

redevelopment programs have announced a large-scale demolition of old buildings,

planning to make way for new constructions. This gives rise to the need for

management of DW, which is generated in the demolition process.

This study will focus on the processes of DW management for the urban

redevelopment projects (Figure 1-1). It also analyses the decision-making process of

DW management at the district level and explores the tool of Geographic Information

System (GIS) to assist stakeholders in improving the decision-making process.

Urban changes ‐ Population ‐ Urbanisation

Urban decay/dilapidation

Urban redevelopment

Economic issues Environmental issues Social issues


This research is also necessary for the practitioners and researchers in the decision-

making process of integrated DW management, as it will assist them to increase the

recovery rate, to ameliorate the environmental impacts and to guarantee the

sustainability of the urban redevelopment.

1.3 RESEARCH PROBLEM

According to Yau and Ling Chan (2008) and Munoth et al. (2013), the concept of

sustainability corresponds to urban redevelopment in terms of environmental,

economic and social aspects. Nevertheless, Zheng et al. (2014) conclude that most

research focused narrowly on one or two aspects of sustainable urban renewal at a

time. While other urban redevelopment issues are seriously considered, such as

heritage conservation, housing development and resident relocation (Fang & Zhang,

2003; Yeoh & Huang, 1996), waste management was not managed in a comprehensive

manner. DW management has received much attention over the last two decades as

one of the main indicators of sustainable urban redevelopment. However, DW

management knowledge and experience in urban redevelopment projects are still

limited.

DW management in urban redevelopment project requires the effective engagement

of a wide range of stakeholders, such as planners, policy makers, constructors, sub-

constructors and the members of wider communities (Poon, et al., 2001). A successful

strategy to integrate the DW management process is to incorporate all key stakeholders

into the demolition process (del Río Merino, Azevedo, & Gracia, 2009; Poon, et al.,

2001; Poon, et al., 2004). This requires an application combining the information and

knowledge of waste management in order to provide a decision-making framework

Figure 1-1: Research focus


throughout the process. This will ensure that the responsibilities are clearly defined,

assigned and allocated to the right stakeholders, which will save time and the cost of

the DW management process.

Despite the negative influences of the DW stream, there is still a dearth of accurate

information compared to construction waste data, especially in developing countries

(Wu, Ann, Shen, & Liu, 2014). This is because DW is often studied under the term of

“C&D waste” or is even mixed up with municipal solid waste. This has led to limited

understanding of DW management, especially DW as a result of urban redevelopment

projects.

In addition, there is a lack of stakeholders’ interest in dealing with DW, since it costs

money and time. There is the need to identify how decisions are made, who could be

involved in this process and their relationships in effective DW management. A clearly

planned DW management is advisable for stakeholders. Thus, it is significant to

identify the decision-making factors affecting DW management and develop a

decision support system to facilitate the DW management process.

Through a case study in Hanoi, the framework of the decision-making process and

decision support system is proposed with a view to closing the substantial gap as

mentioned above. The research results would assist the decision-makers in identifying

the most effective approach of DW management with respect to different criteria.

The mixed-method research comprised a large sample of key industry stakeholders

involved in the DW management process. As an empirical contribution, this work

provides a greater insight into how to improve DW management processes and support

decision-making, particularly considering the unique challenges faced in urban

redevelopment across developing nations.

1.4 RESEARCH QUESTIONS

In view of the research background and research problems outlined in the previous

sections, three research questions are raised to direct the researcher in achieving the

research aim. The research examined the following questions:

(1) What are the key decision-making factors influencing demolition waste

management in Vietnamese urban redevelopment projects?


The selection of appropriate solutions and tools towards making decisions for DW

management in urban redevelopment projects depends largely on the perspectives and

consideration of key stakeholders with regards to integrated waste management.

Therefore, considered decisions made from the key stakeholders’ perspectives are

investigated via the first stage of the research – the large scale survey.

(2) How do the key decision-making factors influence demolition waste management

in Vietnamese urban redevelopment projects?

It is essential to understand how the key decision-making factors influence the

improvement of DW management in Vietnamese urban redevelopment projects. There

is limited existing research on DW management, especially in developing countries,

in the context of urban redevelopment that identifies and investigates the critical

decision-making factors and various decision support tools to provide a valid platform

for this research. This research question is investigated via the second stage of the

research: the interview program.

(3) What is the necessary information to support key stakeholders in demolition waste

management in Vietnamese urban redevelopment projects at the district level?

To facilitate effective DW management in urban redevelopment projects, key

stakeholders require requisite information to support their making decisions on DW

management. This is necessary in terms of guiding decision makers to implement

appropriate strategies and actions. The information system should be able to be

assessed and analysed by every stakeholder in different projects at the district level.

1.5 RESEARCH AIM AND OBJECTIVES

The aim of this research is to establish a comprehensive decision-making framework

for improving DW management in Vietnamese urban redevelopment projects at the

district level. The research will explore the key factors that need to be taken into

account and identify the necessary information to support the decision-making process

of DW management with respect to balancing the environmental, economic and social

targets.

In order to achieve the research aim and address the research questions above, three

main objectives are identified:


(1) To explore the current DW management in urban redevelopment projects and in

the context of Vietnam.

‐ Establishing the link between urban redevelopment and sustainability;

‐ Exploring the status of DW management in urban redevelopment projects;

‐ Revealing the existing research and decision tools on DW management;

‐ Examining the context of DW management in Vietnam urban redevelopment

projects;

‐ Investigating the key influencing factors of DW management.

(2) To identify critical decision-making factors of DW management in urban

redevelopment projects.

‐ Investigating the different concerns and expectations of key stakeholders in

making decisions on Vietnamese urban redevelopment DW management;

‐ Identifying the critical decision-making factors in achieving effective DW

management;

‐ Investigating the action plans for each critical factor to enhance urban

redevelopment DW management in Vietnam.

(3) To develop a decision-making framework and critical supporting information to

assist decision makers in improving demolition waste management in Vietnamese

urban redevelopment projects at the district level.

‐ Identifying the necessary information to support decision makers in the

decision-making process of urban redevelopment demolition waste

management;

‐ Developing the supporting database of DW management at district level in

GIS-based model for an applied case study in Vietnam

‐ Integrating a decision-making framework with a GIS-based system for

improving DW management in Vietnamese urban redevelopment projects

with respect to sustainability at district level;

1.6 RESEARCH SIGNIFICANCE

Along with the overall growth of the world's population and continuing urbanisation

process, large-scale housing and urban redevelopment activities are taking place in

many cities throughout the world in order to upgrade housing conditions and urban


infrastructure. As a result of the growth of urban redevelopment, DW volumes are

predicted to keep rising. This poses challenges for many urban areas facing a shortage

of capacity landfill and a potentially severe environmental impact.

The demolition of existing buildings is a predominant feature of urban redevelopment,

therefore its waste management is particularly important. DW management has

received much attention over the last two decades as one of the main indicators of

sustainable construction (Munoth, et al., 2013; Qualharini & Flemming, 2009; Yau &

Ling Chan, 2008). However, there has been limited research on DW management in

the context of urban redevelopment. Although developing countries have experienced

problems of DW caused by urban redevelopment, they seem to be comparatively less

active in DW management research.

This study will investigate the research trend and existing decision tools of DW

management in urban redevelopment projects. This study subsequently uncovers the

list of key stakeholders’ considerations of urban redevelopment DW management with

respect to technical, environmental, social, economic and institutional aspects. The

critical decision-making factors are discussed to provide valuable information for

decision makers in urban redevelopment of DW management. The decision-making

framework in urban redevelopment of DW management is the outcome of the research.

In addition, the decision support system is developed by GIS-based model will

facilitate stakeholders making decision of DW management.

This study will further contribute by offering the framework for other developing

countries that have similar circumstances of urban redevelopment of DW

management, such as China, Thailand, India and Brazil.

1.7 OVERVIEW OF RESEARCH METHODOLOGY

Research design is a plan for undertaking research to answer the research questions by

adopting appropriate and feasible methods (Sproull, 2002). Fellow & Liu (2015) stated

that choosing the research methods requires the logic and relationship between data

collection analysis and the research questions. The body of knowledge can be

developed with confidence only when proper methodologies are employed with

thoroughness (Fellows & Liu, 2015)..

In this study, a decision-making framework is established to support the process of

DW management in the urban redevelopment practice. Therefore, a mixed method is


employed to enable the researcher to review the current situation, identify the critical

decision-making factors and develop the decision support system in order to achieve

the research objectives. Qualitative and quantitative approaches can be applied in

different forms according to different research stages. Four main research methods are

adopted in this study, including literature reviews, questionnaires, semi-structured

interviews, and case study. Table 1-1 presents how the research methods were used to

address the research objectives.

Table 1-1: Research methods are used to address the research objectives

Research objectives

Research methods

To explore the current DW management in

urban redevelopment projects and in the context of Vietnam

To identify critical decision-making factors of DW

management in urban redevelopment projects

To develop a decision-making framework and

critical supporting information in improving demolition waste management in Vietnamese urban redevelopment projects at the district level

Literature review X

Questionnaire X X

Semi-structured

interview X X

Case study X

In the preliminary stage, the interdisciplinary literature associated with urban

redevelopment, DW management and sustainability was reviewed to identify the

research gaps and establish the theoretical framework. The questionnaire survey was

employed to determine the concerns and expectations of key stakeholders in making

decisions about DW management in urban redevelopment projects. With the aid of the

quantitative analysis of questionnaire survey results, critical decision-making factors

were formulated to develop a conceptual framework. In this research, the semi-

structured interview approach was subsequently employed in the qualitative analysis

for more in-depth understanding of the critical decision-making factors.


The supporting database was developed by GIS-based solutions for an applied case

study to practically formulate the DW management database and to illustrate the

feasibility of the framework. This database is based on the critical factors and action

plans revealed in previous stages and is integrated into the decision-making framework

of DW management for the case study of urban redevelopment projects in Hanoi,

Vietnam.

1.8 SCOPE AND LIMITATIONS OF THE RESEARCH

This research was designed to develop a decision-making framework targeted at DW

management for Vietnam’s urban redevelopment projects. Particular emphasis is

placed upon DW in the redevelopment projects of aging buildings, which are

demolished because of urban decay.

The research first explores the research gaps and theoretical framework based on

existing international studies on urban redevelopment DW management. This research

then focuses on investigating key stakeholders’ perspectives about decision-making

factors that influence urban redevelopment DW management with respect to

sustainability. The key stakeholders participating in this research are categorised into

five main groups: academics/researchers, planners, consultants, engineers and policy

makers. The respondents of the questionnaire survey and interviews are from different

backgrounds and play various roles of DW management in the urban redevelopment

projects.

Research data was collected in three main cites in Vietnam, namely Hanoi, Hai Phong

and Ho Chi Minh city, which have witnessed the process of urban redevelopment. Four

urban redevelopment projects in Hanoi are chosen as a case study to develop DW

management database. The research results are, therefore, applicable in Vietnam only

because the case study is limited to a particular set of decision-making factors.

1.9 OUTLINE OF THE THESIS

This thesis consists of eight chapters. A brief summary of each chapter is outlined as

follows. Chapter 1 begins with the introduction section, which describes the direction

of the research. It also explains the research background and research problems. Then,

research questions are raised before the research aim and objectives are formulated.


Finally, Chapter 1 discusses the research significance, research methodology, research

scope and limitations.

Chapter 2 reviews the current theory and former studies relating to the research topic.

The topics covered include the concept of urban redevelopment and sustainable urban

redevelopment, DW management in urban redevelopment projects, and the theory of

decision-making. The theoretical factors that influence the decision-making process of

urban redevelopment DW management are subsequently identified in this chapter.

Chapter 3 delivers the methodology of the research. It presents the research design

before describing the selected research methods. Research development is composed

of qualitative and quantitative analysis, including a literature review, questionnaires,

interviews, and case study. Ethical considerations are also provided at the end of the

chapter.

Chapter 4 presents the quantitative analysis of the survey data and the findings of the

questionnaire survey. It discusses the questionnaire design, the survey instrument, the

survey response rate and the respondents’ profiles. The key stakeholders’ perspectives

of decision-making factors influencing urban redevelopment DW management are

then identified. The main findings from the questionnaire survey are outlined and the

conceptual framework is also revised.

Chapter 5 illustrates the qualitative analysis of the interview data and the findings of

the interviews. The selection of interviewees and their profiles are briefly introduced.

The interview instruments and structures are then presented before findings and action

plans based on the interview are outlined.

Chapter 6 introduces the GIS-based approach for an applied case study to practically

formulate the supporting database of DW management in Vietnamese urban


Chapter 7 discusses the findings from the data analysis of the questionnaire survey and

interviews, which encapsulates the decision-making framework. The results of

supporting database of DW management are then discussed. Accordingly, the

decision-making framework is finalised.

Chapter 8 sketches the research findings in relation to the research objectives and

research questions. The research contributions and limitations of the research are also

highlighted before future directions are recommended.


1.10 SUMMARY

This chapter provides an overview of the research. It first reveals the research

background and research problems regarding urban redevelopment DW management.

The research aim and objectives are clearly defined to address the research questions.

This is followed by an explanation of research significance and the introduction of

research methods to be adopted to achieve the research objectives. The scope and

limitations of the research are subsequently defined to ensure the focus of the research.

The chapter concludes by providing a summary of the thesis structure and outline.

12 Chapter 2: Literature Review

Chapter 2: Literature Review

2.1 INTRODUCTION

This chapter presents an overview of previous work on related literature and studies

done by the researchers that provide the fundamental background for the research

questions. The first section presents an overview of urban redevelopment on the global

scale and the linkage between urban redevelopment and sustainability. It then reviews

the current DW waste management practices. This is followed by the status of DW

management in urban redevelopment projects, including the current research trend of

urban redevelopment DW management. In this chapter, the need of urban

redevelopment in Vietnam is described based on both the documents and policy

analysis, followed by the review of C&D waste management in Vietnam so that the

main obstacles of DW management implement are revealed. As a result, a decision-

making framework of improving DW management is developed for Vietnam as the

primary purpose of this study. In the following section, a summary of contextual gaps

is discussed to fill the research aims and objectives. On the basis of these discussions,

the identified factors and conceptual framework for improving urban redevelopment

DW management are proposed, after a thorough review of organisational decision-

making is presented.

2.2 URBAN REDEVELOPMENT

2.2.1 Definitions

Urban redevelopment is an inevitable part of modern urban planning (Thomas &

Hwang, 2003), because it is an imperative step for cities to tackle the issues of social

and economic developments. Urban redevelopment projects began to emerge in the

United States in the second half of the nineteenth century (Gotham, 2001) but a

normative concept originated in the British urban policy (Imrie, Lees, & Raco, 2009).

Many studies have pinpointed two main reasons behind urban redevelopment.

Firstly, increasing population in the city centres coupled with poor living conditions

in aging neighbourhoods have called for urban redevelopment (Bernt, 2009; Couch,

1990; Zielenbach, 2000). There are a number of countries that have experienced

economic and population growth, pressurising the need for urban redevelopment.

Chapter 2: Literature Review 13

Secondly, disinvestment and population loss have led to abandoned and dilapidated

infrastructure; redevelopment is therefore required to tackle these shrinking cities

(Couch, 1990). In the early 20th century, this problem exclusively occurred in Europe,

where about 30% of all cities in this continent experienced population declines (Turok

& Mykhnenko, 2007). For example, Germany has been facing dramatic losses of

inhabitants that dramatically has increased the vacancies in housing stock (Deilmann,

Effenberger, & Banse, 2009) and this has led to an increase 0.5% per year of

demolition rate for redevelopment projects.

No consensus yet exists regarding the definition of urban redevelopment in the

literature. Many countries and regions have discussed this concept in such different

terms as “neighbourhood rehabilitation”, “urban improvement scheme”, “in-situ

redevelopment” and “urban regeneration” (Holcomb, 1981). More recently, Zheng, et

al. (2014) indicated that the terms closely related to the concept of urban

redevelopment are ‘urban regeneration’, ‘urban renewal’ and ‘urban rehabilitation’.

Couch, Sykes, and Börstinghaus (2011) indicate that urban renewal and urban

regeneration are similar in meaning and their works are on a relatively large scale.

While urban renewal is considered to be the activities of slum clearance and physical

redevelopment, urban regeneration involves resolving multi-faceted issues in deprived

urban areas to upgrade the economic, social, physical and environmental conditions

(Ercan, 2011). De Sousa (2008) compares that urban redevelopment is more specific

and is conducted on a smaller scale and this term refers to constructing new buildings

on the same site with the demolished, aging buildings. Urban rehabilitation is

refurbishing to a good function (Zuckerman, 1991). Zheng, et al. (2014) conclude that

urban renewal aims to improve the physical, social, economic and ecological

conditions of urban areas by different plans of redevelopment, rehabilitation and

heritage preservation. Although these activities may vary in form and process, the

mutual aims are to promote land-use value and improve the environmental conditions

(Adams & Hastings, 2001); to address the urban decline and urban decay problems

and meet a number of socioeconomic modern goals (Lee & Chan, 2008a).

Urban redevelopment is a construction process wherein the existing aging buildings

are removed and the cleared sites for the construction of new buildings are reused

(Miller, 1959). This approach to the concept of urban redevelopment is applicable to

buildings in seriously dilapidated condition and ones that have no preservation value,


or the design of buildings have poor living conditions (Miller, 1959). In the urban

redevelopment process, developers can make profits by selling the new centrally-

located apartments, and the local government can maximum the land-use value and

enhance the building’s functions, such as in higher living conditions and more

commercial activities in the inner-city (Broudehoux, 1994).

Fong (1985) defines urban redevelopment as a continuous process of physically

restructuring the old part of the city via planned or unplanned programs in both private

and public sectors. De Sousa (2008) indicates that urban redevelopment is new

construction, rebuilt on a site of aging buildings on a small scale and more specific

than others. For example, in the 1980s, in the large-scale urban renewal projects

conducted by the US government, the term of urban redevelopment was used for many

small-scale projects focusing on the improvement of old neighbourhoods and

transportation infrastructure (Ho, 2012). Yeh (1990) elaborates urban redevelopment

as ‘an important process in changing land use and improving the building stock and

environment of a city’ (Page 361). Ng (1998) specifies that urban redevelopment is

one of the strategies of urban renewal, which involves reshaping the older section of

the city in terms of both physical and social fabric.

Based on the definitions mentioned above and the context of this study, urban

redevelopment is understood as a process that involves demolitions of aging buildings

to upgrade the physical and socio-economic conditions in order to meet the modern

standard and constructions of new buildings on the same site, including resident and

non-resident buildings. It highlights the fact that aging buildings are dilapidated blocks

scattered in a city core with high density of population.

In summary, urban redevelopment is highly desirable for modernising an old city core

in achieving a number of goals, such as slum clearance, provision of accommodation,

reform of population mix, encouragement of economic growth, effective land-use,

rectification of construction shortages and improvement of neighbourhood (Chan &

Lee, 2008b). However, Kazemian (1991) indicates that dismantling the structure of the

old building is the most serious concern of the urban redevelopment process, triggering

problems such as the ruin of cultural heritage, the destruction of the neighbourhood

regarding social and psychological loses, and the impact on other functionary social

systems. Therefore, the issues of social, environmental and economic impacts should

be wisely considered in the urban redevelopment process.


2.2.2 Global trend in urban redevelopment

As the world population grows and urbanisation increases, massive housing and urban

redevelopment activities take place in many cities over the world. The World Bank (as

cited in Dowall, 1994) reported that there are over 30% of urban households living in

poorly equipped accommodation with a low living standard, with less than 4 square

metres per person, and approximately 28% are classified as those living with no

sanitary facilities. There were almost one billion people living in urban slums, which

are overcrowded, polluted, insecure and lack basic necessities such as clean water and

sanitation (Habitat, 2006). According to the United Nations Human Settlement

Program (Habitat, 2006), these urban slums are projected to double by 2030, placing

pressures on cities around the world. These require the redevelopment projects to

provide more living space and improve the living conditions, both of which help

transform urban space into high-rise building or reshape the purpose of land-use

(Dowall, 1994; Ercan, 2011).

In addition, the dilapidation in most cities has been significant to the extent that it has

urged cities to improve their performance to meet the urbanisation criteria (Steinberg,

1996). For example, Steinberg (1996) indicates that the large quantity of aging

buildings in cities of developing countries that were built before the 1970s have been

considered the housing problems that need to be addressed. At the same time, the

desire for urbanisation has led to the change of the cities in socio-economic respects

by the elimination of the aging buildings in the city core. Wu and He (2005) indicate

that urban redevelopment has often been carried out in the most dilapidated areas and

the oldest part of the city, because the high population density and building density

hinder the extensive redevelopment of the whole city. Recently, the governments of

many countries have paid more attention to urban redevelopment, which is reshaped

on a large scale in order to upgrade housing conditions and urban infrastructures.

The earliest urban redevelopment projects were implemented in the United States in

the late 19th century and increased in quantity in the 1950s in developed nations after

World War II (Demberel, 2010). The first urban redevelopment efforts in the United

States instigated the American Park movement and the City Beautiful movement,

which focused on the transformation of city cores by the incorporation of public parks

and monumental buildings (Holcomb, 1981). In the 1930s, the programs of Public

Works and Public Housing was conducted to transform the slums, blighted areas and


low-income housing to modern complex apartments (Nelson, 1988). In the 1960s, the

small-scale urban redevelopment programs were promoted in order to improve urban

conditions (Holcomb, 1981). According to America’s national report in 1992, 86,000

housing units accounting for 6% of public housing were dilapidated and in need of

redevelopment (Leigh & Patterson, 2006). It is estimated that about 1.8 million US

housing units were demolished in the 2000s (Farfel, et al., 2005). From 2000 to 2004,

about 6,000 buildings were razed in the city of Philadelphia and many industrial cities

in the US faced the problems of demolishing thousands of abandoned buildings, such

as Baltimore, Michigan and Detroit (Leigh & Patterson, 2006).

In Europe, Grebler (1964) argues that the modernisation of the old city cores emerged

in the industrial revolution in Europe, which was later than that in the United States.

In the late 1960s, the renewal policies were formulated to implement slum clearance

and action plans placed emphasis on rehabilitation (Couch, 1990). After the Second

World War, the quality of most of the housing stock in Europe did not meet the

requirements of contemporary society (Itard & Klunder, 2007). For example, old

buildings in most urban districts in the Netherlands failed to meet the living standard

in size and divergent usages, leading to massive demolition and reconstruction.

In Eastern Germany, due to shrinking population, the demolition rate increased to

0.5% of the existing stock per year in the early 2000s and this figure is expected to rise

more noticeably in the next 40 years (Deilmann, et al., 2009). According to Deilmann,

et al. (2009), western Germany will paint a similar development scenario in another

25 years. In the program launched by the German Federal Government in 2007, there

are about 30 million pre-1984 units in Germany that will be upgraded by 2020 (Power,

2008).

In the middle of the 20th century, the UK faced the physical problems of replacing the

old sections of cities to improve housing and living conditions from the low level to

the approved higher regional levels (Couch, 1990; Ho, 2012). The UK government

offered the guidelines for urban redevelopment plans in the city cores (Couch, 1990).

This presented the physical problems of the old areas in improving housing and living

standards. From 1930 to 1980, the slum clearance programme was conducted with

massive demolitions in Britain, and in the late 1960s this culminated in about 80,000

demolitions per year (Power, 2008). According to Power (2008), a maximum of two

million London homes are forecast to be demolished by 2050 and about 10% of current


stock is estimated to be razed by then. In Ankara, Turkey, urban redevelopment

projects were the main solutions to address the issues of squatter settlements since the

1980s, which were shelter to 75% of Ankara’s residents (Uzun, 2005).

The strategy of urban renewal was also adopted in Hong Kong, China and Singapore,

with a focus on tackling poor housing conditions and urban decay in the city cores. In

the early 1970s in Hong Kong, a huge programme of urban redevelopment was

implemented in order to remove resettlement buildings by modern city infrastructure

and the urban redevelopment was conducted to replace the dilapidated buildings in the

old districts with new apartments (Yeh, 1990). In the late 1990s, it was estimated that

about 80 hectares of land-use in the inner-city needed redevelopment (Hui, Wong, &

Wan, 2008). According to an assessment by The Planning and Lands Bureau of Hong

Kong in 1999, roughly 2,200 of the total 8,500 buildings aged over 30 years needed to

be redeveloped or intensively repaired and another 3,900 buildings required repair on

varying scales (Poon, et al., 2004).

In Hong Kong, it is also estimated that the number of buildings constructed over 30

years will reach by 50% in the following 10 years. These issues can be found in many

districts where many dilapidated buildings awaited improvement or redevelopment

(Yau & Ling Chan, 2008). In 2001, the Hong Kong Government set up the Urban

Renewal Authority to implement 225 urban redevelopment projects, which cost more

than US$38 billion (Mui & Sankaran, 2004). The number of buildings that were

redeveloped in the early 2010s was recorded at 879, including both residential and

non-residential buildings (Hui, et al., 2008). It is reported that 10,000 buildings aged

over 30 years and 7,500 aged over 40 years were in need of urban redevelopment

efforts in 2006 (Hui, et al., 2008). Hui, et al. (2008) pointed out that the large number

of existing ageing buildings in Hong Kong can be a major issue to urban decay and

will take hundreds of years to be redeveloped.

Furthermore, in China, the scale of urban redevelopment and residential relocations

has been extensive (Li & Song, 2009). There were 8.5 million households relocated in

the 1980s and the pace of urban redevelopment began to accelerate in the 1990s (as

cited in Li & Song, 2009). A study by Fang and Zhang (2003) also indicate that

growing population in the inner city led to a redevelopment program of about 4.2

million square metres in four districts located in Beijing in 1998. In the 10-year period

between 1995 and 2004, over 33 million square metres of housing were redeveloped


in Shanghai, a project which is larger in scale than urban renewal projects in cities of

the USA (He & Wu, 2007).

In the Ninth Five Year Plan from 1996 to 2000, it is reported that about 330 million

square metres of housing were demolished throughout the whole of China (Li & Song,

2009). This urban redevelopment program in China covered most of the traditional old

houses aged up to 100 years old or lane housing with simple structures (Fang & Zhang,

2003; Li & Song, 2009). However, studies on urban redevelopment in China are more

focused on the preservation of historical buildings, the relocation of populations and

the resolution of political-economic problems (Li & Song, 2009). In line with that, the

environmental issues associated with urban redevelopment programs have also been

recognised in Beijing (Fang & Zhang, 2003).

The Land Title Act was introduced in Singapore in the year 1999, with the aim to

encourage private sector engagement in urban renewal (Hui, et al., 2008). This decree

has made vital contributions to the redevelopment of aged buildings and the provision

of new housing apartments. There were over half a million square metres redeveloped,

which covered about 7,400 residential apartments. In 2000, the Singapore’s Urban

Redevelopment Authority was established to enhance redevelopment activities and

motivate housing development (Hui, et al., 2008). By doing this, Singapore has

improved the conditions of living and physical environment, and has conserved

landscapes and built modern infrastructure.

Similarly, Seoul experienced significant population growth, which reached

approximately 9.64 million after the Second World War in 1985, requiring a huge

demand for housing and urban development (Ho, 2012). The urban redevelopment was

adopted in the early 1960s, aiming to provide commercial and office uses, particularly

in Seoul (Ha, 2001). The very first urban redevelopment activity was to deal with the

problems of the clearance of squatters and improve housing conditions (Sohn, 2003).

According to Ha (2001), a Joint Redevelopment project was introduced to Korea in

1983, which heightened housing standards by building high-rise flats, with height

varying from 15 to25 stories. In 1984, the Seoul government established the guidelines

for Joint Redevelopment to facilitate the urban redevelopment process led by

stakeholders of the corporation (Ho, 2012).

However, Ho (2012) states that this program lacked comprehensive planning and the

focus was on a small scale, rather than on a district level. Moreover, apart from the


first Seoul Comprehensive Plan introduced in 1990, the Seoul government has

improved the urban redevelopment program to upgrade living conditions in the old

districts and improve the residential environment (Ho, 2012). According to the

Ministry of Land, Transport and Marine Affairs, South Korea, the project of urban

redevelopment has led to a replacement of 67,000 housing units that had been located

in over 200 districts (Ho, 2012). Of those urban redevelopments in Seoul, most of the

houses had been in very poor condition in terms of structure, materials and facilities

(Ha, 2001).

Australia witnessed intensive urban redevelopment after the Second World War

(Arthurson, 1998). Arthurson (1998) states that the majority of public housing was

aging and had poor design. In addition, the demographic change and the economic

development have put pressures on urban redevelopment. As a result, many urban

redevelopment projects have been operating on a large scale in Sydney, Melbourne,

and other cities, since the 1990s.

The pace of urban redevelopment in other developing countries, such as Brazil, India,

Vietnam and Thailand, is still slower than in developed countries. In the 1970s and

1980s, the major goals of urban redevelopment in developing countries are addressing

the issues of urban slum and squatter eradication (Broudehoux, 1994). There are

numerous problems of aging buildings in the city cores such as misusing land, lacking

community facilities, poor living conditions and high residential density (Ng, 1998).

Thus, these problems can be addressed through urban redevelopment programs,

focusing on upgrading the old buildings in the city cores to modern buildings.

The rate of urban redevelopment in many countries is a natural development in

urbanisation and economic growth. Consequently, urban redevelopment plans need to

be embedded in a long-term scenario of urban development in the modern city. The

redevelopment activities must be undertaken with the combination of economic,

environmental and social targets aiming to achieve sustainability. Fang and Zhang

(2003) indicate that urban redevelopment is a profound value-laden process involving

societal engagement. Therefore, the issues related to the environment, economy and

society should be considered by all concerned in the public domain, with respect to

sustainable development.

For several decades up to now, the environmental consideration in urban

redevelopment and urban renewal has been waste implication. Although large-scale


urban redevelopments may drive profit, they have also profound impact on the

neighbourhoods and the historic environment (Wu & He, 2005). The consensus

between researchers is that urban redevelopment practices have been conducted with

too much attention on economic objectives and have neglected the environmental and

social issues, which evidently violates the global trend of sustainable urban

development (Chan & Lee, 2008b; Wu & He, 2005). Thus, there is a need for emphasis

on DW in urban redevelopment activities, which poses environmental pressure on

sustainable urban development. The next section will provide the discussion on the

link between urban redevelopment and sustainability.

2.3 THE LINK BETWEEN URBAN REDEVELOPMENT AND SUSTAINABILITY

In a well-known statement of the Brundtland Report (WCED, 1987, p. 16), sustainable

development is defined as ‘development that meets the needs of the present without

compromising the ability of the future generation to meet their own needs’ (Page 16).

This perception can be understood as improving the quality of life to provide people

with a healthy environment and enhance the social, economic and environmental

conditions for present and future generations (Ortiz, Castells, & Sonnemann, 2009).

There is a growing body of literature that has strongly attempted to conceptualise

sustainable construction in different contexts. The construction industry is considered

as a major contributor to the environmental issues due to the extraction of raw

materials and generation of waste in its manufacturing process. Zimmermann, Althaus,

and Haas (2005) give evidence that the construction sector is a source that consumes

a large amount of energy, generates waste, increases global greenhouse gas emission,

creates different types of pollution, and triggers environmental problems and natural

resource depletion.

As the challenge of sustainability was associated to the construction industry in the

early 1990s, the new disciplines of ‘sustainable construction’ of ‘green construction’

were discussed at The First International Conference on Sustainable Construction in

Florida, the United States of America in 1994 (as cited in Hill & Bowen, 1997). The

term of ‘sustainable construction’ refers to ‘cradle to grave’ assessment, which

comprises managing the serviceability of a building and recycling of building


materials to reduce demolition waste (Wyatt & Gilleard, 1994). Manowong (2012)

argues that environmental sustainability is essential to construction management,

which includes construction waste management and pollution control. While social

sustainability provides a better living condition, the issues of construction waste are

addressed. In addition, in terms of economics, sustainability can be only achieved

when the living conditions are improved and the environment is enhanced.

Accordingly, urban redevelopment has a substantial impact on all three aspects of

sustainability: the society, the economy and the environment, which requires a

significant consideration of achieving a more sustainable society (Lombardi, Porter,

Barber, & Rogers, 2011). Urban redevelopment is consistent with the goals of

sustainability, because it helps encourage compact development, reuse existing

infrastructure, and support local businesses and employment (Leigh & Patterson,

2006).

The concept of sustainable development was first integrated in the UK urban

redevelopment plans in the 1990s (Ho, 2012). In sustainable development: the UK

strategy in 1994, the government realised the significant contribution of urban

regeneration to sustainability that uses developed areas in the effective way, while

creating them more attractive places of living and working (Couch & Dennemann,

2000).

According to Couch and Dennemann (2000), urban regeneration contributes to

sustainability by recycling dilapidated areas, reducing the demand for peripheral

development and facilitating the development of modern cities; however, it still needs

to fully tackle the requirement for other aspects of sustainability, such as community

participation, pollution issues, employment for inhabitants, and waste and resources.

In 2001, the Hong Kong government had considered the concept of sustainable

development in planning and executing urban renewal programs, however such a

concept still needs to be improved in terms of balancing the social aspects (Chan &

Lee, 2008a).

Recently, academic scholars have endeavoured to pay more attention to sustainable

urban redevelopment to balance economic, social and environmental issues (Leigh &

Patterson, 2006; Munoth, et al., 2013; Yau & Ling Chan, 2008; Zheng, et al., 2014).


According to the studies by Yau and Ling Chan (2008) and Munoth et al. (2013), the

indicators of urban sustainable redevelopment have been recognised based on three

dimensions of sustainability, as shown in Figure 2-1. Thus, urban redevelopment

mainly aims at solving the urban decay, and it also needs to meet socioeconomic

targets and resolve environmental problems (Zheng, et al., 2014).

Figure 2-1: Triple bottom line of sustainable urban redevelopment

Social sustainability is to improve the living conditions, to conserve the urban heritage,

to enhance the urban facilities and to relocate successfully the housing residents.

Economic sustainability is to implement cost-effective urban redevelopment projects,

to promote job creation, to design efficient infrastructure systems and to increase land-

use values. Environmental sustainability is to efficiently consume the energy in

conducting urban redevelopment projects, to comprehensively manage C&D waste, to

significantly reduce the noise and air pollution and to create more public space.

With respect to the three pillars of sustainability, urban redevelopment can vitally

contribute to sustainable urban development. However, most urban redevelopment

policies have placed much emphasis on economic targets rather than social and

environmental aspects (Couch & Dennemann, 2000; Zheng, et al., 2014), and the

concept of sustainable urban redevelopment is poorly conceptualised. Therefore,

Environment target- Energy efficiency supply

- C&D waste management

- Noise and air pollution management

- Creation public spaces

Social target- Better living conditions

- Conservation of urban heritages

- Better urban facilities

- Sactifaction for relocation

Economic target- Cost effective UR project

- Job creation

- Efficient infrastructure system

- Promote land-use values

Sustainable urban

redevelopment


sustainability needs to be integrated in urban redevelopment policy with greater

accentuation given to environmental considerations, particularly DW management.

2.4 DEMOLITION WASTE MANAGEMENT

2.4.1 The lifecycle of the built environment

The concept of closed-loop in the field of construction industry is rooted in nature’s

ecology (van Dijk, Tenpierik, & van den Dobbelsteen, 2014). As buildings are

constructed by the complexity of natural materials that have their own life spans, such

as wood, steel, concrete, plastics and ceramic, building development is deemed as a

cyclical process that consumes a large amount of energy and materials. Whether the

life span of buildings lasts for long or not depends on different factors, such as the

components’ quality, the purpose of use, the climate and the circumstance of socio-

economy.

Construction lifecycle is described in the study of Kibert (1994) as a process of

planning, development, design, use, maintenance and deconstruction. According to the

framework of C&D waste management, there are six different stages in a project

lifecycle, from the concept to design, construction and operation, to maintenance and

demolition, as shown in Figure 2-2 (Lu & Yuan, 2011). As is illustrated, there is a link

between the demolition stage and the redevelopment stage, and the building’s life

cycle is completed at the demolition stage. It is perceived that at the end of the building

life span, demolition produces a larger amount of waste than other stages (Shen, Li

Hao, Tam, & Yao, 2007).

In the field of construction, researchers and practitioners are trying to find the

alternatives to extend the life of buildings in order to avoid demolition and

environmental impacts, such as maintenance or deconstruction of the old buildings

(Kibert & Chini, 2000; Leigh & Patterson, 2006; Wyatt & Gilleard, 1994). Leigh and

Petterson (2006) argue that deconstruction is a more sustainable approach instead of

the demolition of dilapidated structures and construction of new buildings. This

approach can reduce the amount of waste produced during the demolition process and

through the reuse of the existing buildings.


Figure 2-2: A C&D waste management framework.

Adapted from ‘A framework for understanding waste management studies in

construction’ by (Lu & Yuan, 2011), page 1255.

However, most of the buildings aged over 30 years old have not been designed with

sustainability in mind (Poon, et al., 2004). In addition, overcrowded, dilapidated and

aging buildings in the city cores have become targets for demolition in pursuing

modernity (Liu, Pun, & Langston, 2005a). For instance, the history cityscape of

American cities changed from the late nineteenth century with the urban

redevelopment programmes for slums and blight clearance, and housing development

(Gotham, 2001). In the 1970s and 1980s, Singapore launched urban redevelopment

and renewal projects that encompassed the demolition of blighted and dilapidated

areas to make way for modern high-rise buildings (Lee, 1996). These issues have

occurred in many cities all over the world and have involved not only socio-economic

but also environmental problems.

Shen, et al. (2007) state that the demolition of a structure is considered as the

completion stage of the project lifecycle, which normally generates different wastes

such as wood, concrete, metal, bricks, plastic, gypsum, roofing shingles and glass. It

is suggested that the volume of waste in demolition work is far greater than that from

a new construction project. In addition, research by Itard and Klunder (2007) indicates

that compared with other options, such as maintenance, consolidation and

transformation, demolition and rebuilding (redevelopment option) lead to more

impacts on the environment due to more energy consumption, raw material extraction,


and waste generation. The assessment of environmental effects of a building’s

lifecycle is presented in Figure 2-3 (Itard & Klunder, 2007).

Figure 2-3: Environmental effects as a function of time.

Adapted from ‘Comparing environmental impacts of renovated housing stock with

new construction’ by (Itard & Klunder, 2007), page 255.

According to Liu, Pun, and Langston (2005b), the previous efforts in addressing the

impact caused by DW were mainly focused on the disposal of DW, not the demolition

process itself and full consideration should be given to the last lifecycle stage of

demolition. Thus, an effective approach to DW management is urgently needed to

minimise the environmental effects, by recovering as many of the dismantled materials

as possible.

2.4.2 Integrated approach to waste management in construction industry

The term of ‘integrated’ was first coined in the field of waste management during the

1970s and became standardised by the mid-2000s (Wilson, Velis, & Rodic, 2013).

Wilson et al. (2013) also indicate that integrated waste management are mainly

technical, focusing on how to combine different technical elements into a system, and

the computer-aided tools are used to support with that integration. From the

perspective of sustainability, the research undertaken by Diaz, Savage, and Golueke

(1996) shows that the three objectives of triple bottom lines indicating sustainability

are economic, environmental and social aspects that need to be emphasised in an

approach of integrated solid waste management.

In addition, the government and local authority also need to be taken into account in

those dimensions, such as political, economic, socio and environmental aspects. In the


literature and practice, integrated waste management is understood as an approach to

achieve the goals of sustainability. This is integrated in all fields, and C&D waste

management is no exception. The conceptual model of construction waste

management in achieving sustainability is suggested by Manowong (2012), as

demonstrated in Figure 2-4.

Thus, the integrated DW management could only be achieved when a comprehensive

strategy and solution are proposed based on the interactions between the above three

pillars. The complexity of the system to recognise integrated DW management is

illustrated in Figure 2-5.

Environment

Economic

InstitutionalTechnical

Society

Integrated DW management

Environmental Sustainability

Social Sustainability

Economic Sustainability

Construction waste management

Green and sustainable

i

Figure 2-4: Conceptual model for sustainable construction waste management (Manowong, 2012)


Figure 2-5: System for integrated demolition waste management

Generally, the ‘3R principles’ has been a key concept in C&D waste management,

including DW management, which refers to reduction, reuse, and recycling (Yuan &

Shen, 2011). This guideline has helped researchers and practitioners develop effective

strategies through waste reduction, reuse, and recycling instead of dumping the C&D

waste. Peng, et al. (1997) also suggest a hierarchical classification of waste

management strategies and their environmental impacts from low to high (Figure 2-

6).

‘Reduce’ means measures used, before a building structure or component becomes

waste, that reduce: (a) the quantity of waste, (b) the adverse influences of the waste

generation on the environment and human health, or (c) the content of hazardous

substances. Reduction is the most desirable strategy for controlling C&D waste in

terms of saving natural resources and remedying environmental pollution (Yuan &

Shen, 2011).

‘Reuse’ means any building structures, or components that are not waste, reusing for

the same purpose or other purposes. Reuse also denotes less energy consumption and

the process is not complicated compared to other principles (Peng, et al., 1997). The

C&D waste is usually reused as aggregate in road construction (Hendriks & Janssen,

2001). For example, in the Netherlands, a large portion of C&D waste is reused as raw

materials in road construction, accounting for more than 95% of the total (Mulder, de

Jong, & Feenstra, 2007).

Reduce

Reuse

Recycle

Compost

Incinerate

Landfill

Env

iron

men

tal i

mpa

cts

Low

High


‘Recycle’ means any recovery of waste, whether for the original or other purposes.

Recycle has been widely used as an alternative approach when the waste is hardly ever

reduced and reused. This creates recycled production that can be used in other

constructions (Yuan & Shen, 2011), which reduces the amount of landfilling waste as

well as the effects on natural resources (del Río Merino, et al., 2009). South Korea, as

a salient example of recycling, recorded the recycling rate at 98.1% (Somasundaram

et al., 2015).

2.4.3 Current status of demolition waste

The term of construction and demolition (C&D) waste has been used to refer to the

solid waste resulting from construction, renovation and demolition activities of

structures (Lu et al., 2011). These structures include buildings of all types in residential

and non-residential households as well as roads and bridges. Depending on its

generation phases, C&D waste can be classified into three major categories:

construction waste, renovation waste and demolition waste (Wu & Ann, 2014).

A typical component of C&D waste contains a mixture of inert and non-inert materials.

Inert substances mainly include sand, bricks, and concrete, making up 40% to 85% of

the total (Eurostat, Environment and Energy, 2009). C&D waste, representing one of

the major waste streams, varies significantly from country to country according to the

differences in the economy, culture, perspectives of C&D waste and the way of data

collection (Kourmpanis, Papadopoulos, Moustakas, Stylianou, et al., 2008). It has been

reported that the proportion of C&D waste amounts to 25 to 30% of the total municipal

solid waste in the EU, as opposed to 40% in China, 29% in the USA, 44% in Australia,

and 36% in Japan (Hendriks & Pietersen, 2000; Wang & Yuan, 2008).

In recent decades, the construction industry has been globally considered as the major

producer of solid waste (Marzouk & Azab, 2014; Poon, et al., 2004) and DW is

commonly managed together under the term ‘C&D waste’. However, the

characteristics of waste, resulting from demolition processes, are quite different. The

Figure 2-6: Hierarchy of construction and demolition waste


DW signifies the materials from demolition and clear sites and which structures are to

be dismantled before the erection of new ones (Fatta et al., 2003). DW is composed

of ‘metals (steel, aluminium, copper and zinc), inert wastes (titles, concrete, bricks,

ceramic materials, stones, clinker), wood, plaster, plastic (PVC), flat glass, glass wool,

and hazardous waste (bituminous roof and fluorestives lamps containing mercury)’

(Roussat, et al., 2009b). The DW composition varies according to the type, age, shape,

use, and size of the structure, while the historical, cultural and economic values of the

buildings are very important factors that influence the DW components (Fatta, et al.,

2003). In addition, demolition work generates typically more waste than the

construction one, which requires more attention on effective DW management (Chen

& Lu, 2017; Yuan & Shen, 2011).

Furthermore, the DW characteristics depend on the demolition technologies and

methodologies. For example, the demolition work with heavy equipment generates a

commingled pile of waste that makes classification of reusable waste difficult. (Poon,

et al., 2001). The research of Poon, et al. (2001) also indicates that the recovery rate of

reusable waste is enhanced by using mechanical hand tools, such as ‘piece-by-piece’

wrecking. Therefore, the success of DW management is highly dependent on the

selection of demolition methods.

In general, DW is mostly inert materials (Poon, et al., 2004), though it is likely that the

DW poses less threat to the environment than other types of municipal solid waste

(Wang, Touran, Christoforou, & Fadlalla, 2004). However, from the environmental

perspective, growing evidence has suggested the effects of DW in terms of damaging

natural resources and cityscape by expansion of the landfill spaces, leaching

contaminated substances into soil and water, and increasing air and noise pollution

levels (Yuan, 2011). In addition, construction waste treatments consume large amounts

of energy in transportation and manufacturing (Marzouk & Azab, 2014). For the

reasons above, DW can cause more issues than construction waste, such as

environmental pollution, low rate of recovery, difficulties in waste sorting, and higher

energy consumption for DW treatment. Thus, it is required that a specific study of DW

management should be conducted.

Globally, an average of 28% of municipal solid waste is C&D waste, meanwhile, 10%

that of is reused, and over 60% is recycled and the remaining 30% is disposed of in

landfill (Reddrop et al., 1999; Graham et al., 2003). In Germany, the annual volume


of waste is calculated for DW and construction waste, accounting for 22.6 million

tonnes and 10 million tonnes respectively (Brooks, Adams, & Demsetz, 1994). The

construction industry in Hong Kong accounts for 44% of all municipal solid waste

disposed daily in the landfill (Poon, et al., 2004). Leigh & Patterson (2006) also note

that C&D waste accounts for 25-40% of the US waste stream, 92% of which is from

demolition and renovation activities.

According to Eurostat, Environment and Energy (2009), the European Union generates

an annual average of over 500 million tonnes of C&D waste , accounting for 25 to

30% of all waste streams (Mália, de Brito, Pinheiro, & Bravo, 2013). In Western

Europe, about 175-250 million tons of DW are generated each year, with France

generating explicitly 17 million tons (Roussat, Méhu, Abdelghafour, & Brula, 2008).

The study by Kleemann, Lederer, Aschenbrenner, Rechberger, and Fellner (2014)

indicates that in Austria, there were about 6.5 million tonnes of DW management

generated in comparison to only 3.9 million tonnes of municipal solid waste.

In Australia, C&D waste contributes up to 30-40% of solid waste that goes to landfills

(Liu, et al., 2005b). According to the report by Hyder Consulting (2011) in 2008-09,

C&D waste accounted for about 19.7 million, which corresponded to approximately

42% of the national waste. Further, 49.9% of the solid waste stream in South Korea

was derived from C&D waste (Somasundaram, et al., 2015), while in China, Zhao,

Leeftink et al. (2010) reported that C&D waste constituted more than 30% of

municipal solid waste and Lu (2014) figured out that DW is the largest proportion,

constituting 62.3% of the total C&D waste produced in the year 2011.

In the past, landfilling was the main approach for construction waste management,

including illegal disposal, and this put pressure on landfill sites that could be exhausted

in the short term (Tam, 2008). Río Merino, Azevedo et al. (2009) indicate that in Spain,

the rate of growth in C&D waste was 8.7% yearly in the 2000s and 90% of this waste

went directly to landfill. Facing the large proportion of waste generated from the

construction industry, many countries such as Hong Kong, Australia, China and EU

countries, promoted legislation aiming to minimise the amount of C&D waste in the

landfill (Mália, et al., 2013; Mcdonald & Smithers, 1998; Poon, et al., 2004; Wong &

Yip, 2004; Yuan, et al., 2011).

Reduction is the most desirable strategy for controlling C&D waste in terms of saving

natural resources and remedying environmental pollution (Yuan & Shen, 2011). While


Denmark, the Netherlands, Germany, and The United States have succeeded in the

reduction strategies in C&D waste management, countries such as Hong Kong, China,

India, Greece and Thailand are facing challenges in waste reduction (BIO Intelligence

Service, 2011). As the later countries continue to redevelop, more and more C&D

waste that puts high pressure on the landfill will be generated. Therefore, the need of

creating waste management plans could minimise the amount of waste in construction

projects.

Reuse consumes less energy and its process is not complicated compared to other

principles (Peng, et al., 1997). The C&D waste is usually reused as aggregate in road

construction (Hendriks & Janssen, 2001). For example, in the Netherlands, a large

portion of C&D waste is reused as raw materials in road construction, accounting for

more than 95% of the total (Mulder, et al., 2007).

Recycling has been widely used as an alternative approach when waste is rarely

reduced and reused (Yuan & Shen, 2011). This creates recycled production that can

be used in other constructions (Yuan & Shen, 2011), reducing the amount of landfilling

waste as well as the effects on natural resources (del Río Merino, et al., 2009). Many

studies have indicated that only 25-30% of C&D waste is currently recycled and about

75% of C&D waste dumping in the landfills can be diverted (Biddle, 2001). South

Korea serves as a successful example of recycling with the rate observed at about

98.1% (Somasundaram, et al., 2015).

According to The European Union’s Waste Framework Directive, the requirement for

the average of C&D waste to be recycled and reused in European countries is 70% by

2020 (BIO Intelligence Service, 2011). It is evident that Denmark, Germany, and the

Netherlands have successfully achieved the targets with the level of recovery of C&D

waste accounting for over 80% (Nisbet, Venta, & Foo, 2012), while Spain and Greece

have a recovery rate of below 20% (Brodersen, Juul, Jacobsen, & Tsotsos, 2002).

Some developing economies have contributed noticeably in C&D waste treatment; for

example, Malaysia and China have promoted research efforts in C&D waste

management (Yuan & Shen, 2011), while other developing countries are making

relatively slow progress in recovering, such as India and Vietnam.

Facing the large proportion of waste generated by the construction industry, many

countries such as Hong Kong, Australia, China, Japan and EU countries have

introduced legislation directed at promoting the use of recycled materials and


minimising the amount of C&D landfill waste (Mália, et al., 2013; Mcdonald &

Smithers, 1998; Poon, et al., 2004; Wong & Yip, 2004; Yuan, et al., 2011). The rate

of waste recovery has been improving over the last two decades by means of national

efforts to reduce its impacts on natural resources and the environment. For example,

Denmark, Belgium, and Netherlands have a high level of C&D waste recovery, each

accounting for over 80% of all C&D waste (Brodersen, et al., 2002). Similarly, South

Korea has been successful in recycling C&D waste, with a recovery rate of around

98.1% (Somasundaram, et al., 2015). Despite increased research into C&D waste

management strategies in developing countries (Yuan & Shen, 2011), other nations

such as India and Vietnam are making relatively slow progress (Huy, 2015).

Along with the popularity of urban redevelopment, DW volumes are predicted to

continue increasing that poses challenges for many urban areas which are facing

capacity landfill and potentially severe environmental impacts (Poon, et al., 2004). In

addition, Chen and Lu (2017) argue that demolition work in both developed and

developing countries is considered as an uneconomical activity if the waste is not

properly handled In response to these concerns, more effective DW management is

critically important for ensuring sustainability outcomes.

2.5 DEMOLITION WASTE MANAGEMENT IN URBAN REDEVELOPMENT PROJECTS

2.5.1 Overview of demolition waste in urban redevelopment projects

According to Liu et al. (2005b), ‘building demolition represents the process in which

an erected structure is purposely destroyed to form a diversity of components and

fragments of mixed materials’. Roussat, et al. (2008) indicate that DW occupies a

major proportion of industrial waste of most countries and the majority of this waste,

including concrete, brick, sand, and gravel, is inert. In addition, Yuan & Shen (2011)

point out that demolition produces typically 10-20 times more waste than the

construction process because the nature of each process is different.

Many studies contend that DW is recyclable materials (Fatta, et al., 2003; Huang, Lin,

Chang, & Lin, 2002; Kourmpanis, Papadopoulos, Moustakas, Kourmoussis, et al.,

2008; Poon, et al., 2001; Wong & Yip, 2004). It is also worth noting that some

developed countries, such as Austria, Germany, and The Netherlands, hold a high

recycling rate of C&D waste in targets of reducing waste to landfill, whilst developing


countries that have different socio-economic circumstances might have difficulties in

management of waste from redevelopment projects.

The reason is that dismantled materials from old structures aged over 30 years are less

modern (Poon, 1997). For example, asbestos used to be commonly used as insulation

material, but now is considered as hazardous waste. Materials such as metal, which is

rarely generated in the construction process, make up a significant proportion of the

total dismantled waste from old structures. Masonry, wood, concrete and brick

typically produced more than half of DW management (Poon, 1997). Finally, Poon

(1997) states that DW often contains hazardous waste resulting from paints, fasteners,

adhesives, insulation and bituminous roof and fluorestive lamps. This hazardous

waste, for example, in France, represents a tiny minority at merely 2% of DW, but it

can give rise to environmental risks when it is not properly managed (Roussat, et al.,

2008). These contaminants can be a hindrance to waste recovery because separation

of this waste at source is not easy compared to construction waste, which is normally

new and segregated (Liu, et al., 2005b; Roussat, et al., 2008).

In urban redevelopment projects, demolition of old buildings can generate a massive

waste, in which all materials are mixed together (Poon, et al., 2001). These create a

waste stream that is more expensive and more time-consuming in waste recovery than

construction waste because of the complexity of its components (Lu, Lau, & Poon,

2009). In addition, it may imply that demolition generates more waste that goes to

landfills than construction, although accurate data of DW from landfills or projects are

unavailable (Liu, et al., 2005b).

Therefore, waste streams resulting from the demolition processes of urban

redevelopment projects should be processed separately for the following reasons.

Firstly, the volume and characteristics of DW in dismantling older structures in urban

redevelopment projects is quite different from construction waste. Secondly, DW

potentially contains hazardous materials, such as paint, bitumen and fluorescent lamps

containing mercury (Roussat, Dujet, & Mehu, 2009a), which can be more difficult to

reclaim, reuse or recycle. In addition, urban redevelopment projects consist of many

stages involving different activities, of which the demolition process seems to be

separate and waste management is the responsibility of different stakeholders. Thus,

an integrated approach that can possibly encompass all activities in the process is

desired to meet the waste management target (Yuan, 2011).


The fact that DW information is not well documented in projects or regional level can

be one of the main contributing factors in the DW management decision-making.

Therefore, implementing a comprehensive waste management strategy requires

effectively sharing the knowledge and information of DW between stakeholders, such

as the waste volume and compositions.

2.5.2 Current research trend in urban redevelopment demolition waste management

As mentioned above, DW is a critical environmental issue in the construction industry.

Both developed and developing countries are facing challenges in the form of urban

redevelopments that generate large amounts of DW (Ding & Xiao, 2014). In response,

researchers are attaching more significance to a variety of aspects of urban

redevelopment waste management. The demolition of existing buildings is a

predominant feature of urban redevelopment and therefore its waste management is

particularly important. Research to date, however, has been piece-meal with no

systematic review of the literature. The effort to identify possible solutions towards

DW begins with the review of urban redevelopment DW management in general.

Five major categories of the literature demonstrated the concerns of urban

redevelopment DW management in both the practice and academic discipline: strategy

and solution, decision support, environmental challenges, stakeholder engagement,

and evaluation. The themes generated under each category are shown in Table 2-1.

The contribution of the literature is discussed in the following sections.

Table 2-1: Key reviewed themes

Category Themes

(1) Decision support

Estimation of C&D waste generation; categorisation of building materials; statistical and geographical analysis of demolished buildings; multi-criteria decision analysis for choosing a sustainable DW management strategy.

(2) Environmental challenges

Leaching behaviour of hazardous demolition waste; air pollution; environmental impacts

(3) Stakeholder engagement

Participants’ attitude to on-site waste sorting; residents’ concerns about environmental issues related to urban redevelopment.


(4) Strategy and solutions

Reduction, reuse and recycling DW; on-site sorting of C&D waste; improving C&D waste management; a C&D waste management tool; legislation for DW management; sustainable redevelopment.

(5) Performance evaluation

Cost efficiency of DW management; assessment of the impact of C&D waste disposal.

2.5.2.1 Strategy and solutions

Researchers since 1997 have been occupied with the strategy and solutions for DW

management, covering different sub-topics, namely sustainable redevelopment, and

strategy and solution.

Sustainable redevelopment is the most prevalent topic in the field of urban

redevelopment DW management. Many studies have realised the importance of C&D

waste management to sustainable urban redevelopment, which is perceived as a

sustainable decision-making factor (Couch & Dennemann, 2000; Leigh & Patterson,

2006; Munoth, et al., 2013; Qualharini & Flemming, 2009; Yau & Ling Chan, 2008).

According to (Andersen, 2003), a sustainable redevelopment scheme should

endeavour to reduce social exclusion and increase economic value of urban areas. In

addition, urban redevelopment should contribute to the conservation of architectural

merits and heritage (Jim, 1994) and the protection of natural resources by taking into

account the environmental issues such as waste and pollution management (Yau &

Ling Chan, 2008). Sustainable redevelopment can provide a paradigm shift in

encouraging reuse and recycling of DW, which leads to reducing the use of natural

resources (Qualharini & Flemming, 2009).

The environmental issue associated with C&D waste derives not only from the

increased quantity, but also from the treatment process (Marrero, Solis-Guzman,

Molero-Alonso, Osuna-Rodriguez, & Ramirez-de-Arellano, 2011). In the particular

case of the demolition project, DW management requires an effective strategy to

minimise the volume, and to reuse and recycle materials in order to alleviate the

impacts on the environment and natural resources.

Of all the countries facing urban redevelopment issues, China, Spain, and the United

Kingdom have studied legislation aiming at improving DW management in the context

of sustainability (Marrero, et al., 2011; Petersen, 2004; Rao & Zhang, 2015). The


study by Rao and Zhang (2015) analysed the construction waste issues in an urban

renewal program and proposes the strategy and policies to improve waste

management. In order to encourage the use of recycling materials, Rao and Zhang

(2015) suggest that the recycling market should be developed. In addition, construction

waste treatment should be regulated, such as initiating charging schemes, establishing

a certification system for recycling materials and introducing government green

purchasing catalogues.

In Spain, a legislation of C&D waste management was established in 2008, covering

waste hierarchy from prevention, reuse, recycling, energy recovery and proper waste

disposal (del Río Merino, et al., 2009). However, the issues arising in demolition

projects, such as a low technical demolition process and no special measures for waste

classification in a demolition project, limit the frame implementation. In order to fulfil

the legal frame, del Río Merino, et al. (2009) suggest a DW management plan, which

includes waste estimation, hazardous waste identification, waste classification,

disposal plan, and so forth.

In the UK, despite the optimal practice guideline for sustainable development in the

construction industry, there is still the need for integration of sustainability into urban

renewal, which seeks environmental benefits, financial cost and community

involvement (Petersen, 2004). By this approach, sustainable DW management is a key

component of sustainable urban renewal projects. Accordingly, Petersen (2004)

proposes a tool of strategic C&D waste management to improve the sustainable

development performance of the renewal project, which is based on three main

parameters, namely social, economic, and environmental dimensions. The tool assists

the local authorities, planners, developers, and contractors in achieving cost benefits

by increasing community engagement and cushioning environmental impacts in urban

renewal projects.

Due to the speed of urban redevelopment and the depletion of landfill space in Hong

Kong, Poon, et al. (2004) suggest the strategy of minimising DW generation and

increasing waste recovery rate by implementing on-site waste sorting and selective

demolition. Although these solutions have been applied successfully in the

construction industry, especially in developed countries, there is a need for further

research specifically devoted to the urban redevelopment DW management. This is


because of the dissimilarities in the quality and quantity of waste from the demolition

of aging buildings.

2.5.2.2 Decision support

The second commonly occurring topic is decision support. This research direction has

provided methods for selecting sustainable DW management strategies, applying

computer-based solutions in estimating the amount of DW generation, identifying

demolition materials, and managing DW.

With respect to sustainability, the DW management can be a difficult task, because

many aspects regarding economic, environmental and social issues, which are often in

conflict, must be considered (Roussat, et al., 2009b). In order to clarify the decision,

Roussat, et al. (2009b) employ an application of the ELECTRE III decision-aid method

to choose a sustainable DW management strategy. This method takes into account the

sustainable development, which is relative to economic, environmental and social

issues. Nine options for DW management were analysed based on eight criteria,

namely energy consumption, depletion of abiotic resources, global warming,

dispersion of hazardous substances in the environment, economic activities,

employment, and the quality of residents’ life. Roussat, et al. (2009b) conclude that

the local authorities can develop the demolition building guidelines based on the

choice of DW management strategies.

According to Lu (2014), C&D waste estimation has been significantly highlighted by

policy makers, academics, practitioners, and pertinent parties. For example, the U.S.

Environmental Protection Agency (USEPA, 2009) asserted that one of the main

purposes of the estimation of the amount of C&D waste generated is targeting to

reduce, reuse and recycle waste as part of the waste recovery challenge by managing

waste more efficiently. In essence, scrutinising theory and knowledge about C&D

waste generation is a prerequisite to establishing a proper solution for waste

management (Li, Ding, Mi, & Wang, 2013), which is the most useful approach to

understand waste management in the construction industry (Lu, et al., 2011). However,

the data of C&D waste generation have been collected and only the aggregate figure

was released in certain regions. For example, in 2014, the total construction waste

generated in 27 European countries was 61.8 million tons (EUROSTAT, 2017). The

generation of C&D waste in Vietnam was 28 million tons in 2008 (MONRE, 2011).

Thus, there is the need of waste estimation generated in the demolition works.


Recently, estimating DW generation on urban redevelopment projects has attracted

increasing attention from academics. Poon (1997) states that it is significant to estimate

the average of DW generation daily. Poon proposed a method for quantifying DW

generation from demolition work in Hong Kong based on the existing total floor areas,

measured site areas and the number of stories of the different aging buildings.

Seo and Hwang (1999) estimate C&D waste in Seoul, Korea, using a four-step method.

The first involves calculating the life span of buildings. In the second step, the floor

area of building including construction and demolition is estimated. Subsequently, the

individual intensity units of C&D waste are calculated and in the final step, the future

C&D generation is projected. Of the total amount of C&D waste, Seo and Hwang

(1999) reported that 98% was produced by demolition work, and concrete and brick

are the main components. Ding and Xiao (2014) conducted a study into C&D waste

estimation for the urban redevelopment activities in Shanghai. Meanwhile, the regional

DW generation can be calculated based on the demolished floor area of resident and

non-resident buildings, structure types and waste intensities. The number of DW types

such as steel, concrete, brick, and gypsum were taken into account in the study by Ding

and Xiao (2014).

In line with the studies of determining DW components, Kleemann, et al. (2014)

proposed a method for investigating the waste composition prior to demolition,

composed of four steps. The first step is to collect and analyse all relevant documents

for the materials used to construct the building. In the second step, on-site inspection

is conducted before the demolition of the building. This step comprises the inspections

of building components, such as windows, doors, floor and roof construction, wires,

pipes, etc. Based on the results drawn from documents and on-site inspection, the

database of built-in materials is aggregated. Finally, the collected data are compared

with the given information, which is reported by the demolition contractors to verify

the proposed method.

Research in waste estimation has been increasing, reflecting the potential benefits of

computer-based systems in the identification quantity of DW. For example, Al-Saggaf

and Jrade (2015) develop a model of BIM and GIS to estimate waste generation in

urban redevelopment projects, which are the total volume of DW, the volume of

reusable and recyclable materials, and total loss waste. The estimation of the total

volume of DW is based on the building area and the height of buildings. According to


the statistics of the demolished buildings in Finland between the years 2000 and 2012,

Huuhka and Lahdensivu (2014) calculated the volume of DW for 50 different building

types based on the floor areas and the number of demolished buildings. In addition,

Huuhka & Lahdensivu (2014) developed a GIS-based model to demonstrate the

characteristics, the waste volume, and location of demolished buildings to assist in the

planning of waste recovery in Finland.

The studies of waste estimation open a new door, through which DW generation

volume can possibly be estimated and the feasibility of using computer-based solution

for DW management can be identified. For example, Kleemann, et al. (2014) suggest

that the database about building age, building categories, and specific material

intensities can be gathered with GIS data as a prerequisite for the management of

demolition projects.

2.5.2.3 Environmental challenges

The results indicate that little research has been conducted on the environmental

challenges topic, with several papers involved having discussed such issues as air

pollution and hazardous DW (Farfel, et al., 2005; Power, 2008; Roussat, et al., 2008).

According to Farfel, et al. (2005), demolition work in urban redevelopment projects

can be a large source of Pb pollution, which poses a potential risk for residents and

workers. Farfel found an acute increase in Pb dust fall during residential demolition

works in urban redevelopment projects in East Baltimore. This finding highlights the

need to control and minimise the level of Pb poisoning and heightens the awareness of

demolition-related public health issues for developers, contractors, planners, and

public health agencies.

Regarding the hazardous DW, Roussat, et al. (2008) also report that DW contains the

substances that, after being mixed with inert waste, such as lead-based paint, mercury-

contained in fluorescent lamps, can adversely impact human health and environment.

These hazardous components represent only 2% of the DW in France, but they can be

a high risk for the environment. Roussat, et al. (2008) conduct leaching tests and found

out that some elements exceed the limit value set by European regulations. These

studies demonstrate that it is of paramount importance to classify and remove

hazardous substances before demolition work, in order to limit the risks of pollution

to the environment.


2.5.2.4 Stakeholder engagement

Only two papers are relevant to stakeholder engagement in DW management. Poon,

et al. (2001) conducted a survey to identify the factors affecting the implementation of

on-site waste sorting and analysed the current views of stakeholders in carrying out

on-site waste sorting. According to Poon, et al. (2001), on-site C&D waste sorting

requires less effort and results in a better classification of inert and non-inert waste in

comparison with off-site sorting. However, the result of Poon’s study showed that the

stakeholders are reluctant to implement on-site sorting because of time and labour

demands. With regards to community experiences and perceptions of urban

redevelopment, Bowie et al. (2005) found out that there is a need for earlier anecdotal

reports of community concerns and that there is a vital role of community in addressing

environmental and psychosocial issues. Since the last study of Bowie et al. (2005),

little importance has been attached to stakeholder roles. The responsibilities and

attitudes of stakeholders in the demolition process in promoting integrated DW

management are in need of further study.

2.5.2.5 Performance evaluation

Research into the performance evaluation - vital for improving integrated DW

management - has received hardly any attention from academia apart from two

relevant studies (Lu, et al., 2009; Marzouk & Azab, 2014). One of these focused on

the environmental and economic impacts from the disposal of C&D waste, including

waste from demolition work and rebuilding. Marzouk and Azab (2014) argue that

C&D waste has increasingly serious impacts on the environment, the economy, and

society. Two alternatives for C&D waste management, namely recycling and disposal,

are evaluated by a dynamic model with the aid of STELLA software in the four

following steps (Marzouk & Azab, 2014). The first step is to quantify the total cost of

mitigating the impacts of C&D waste on the environment and human health. Then, the

study quantifies the total emissions avoided and energy saved by recycling waste. The

third step is to estimate the cost saved by recycling waste. Finally, a decision support

tool is provided to assist the re-thinking of waste disposal. Marzouk and Azab (2014)

conclude that recycling C&D waste can significantly reduce the emission, energy use,

global warming potential, and converse landfill area when compared with the disposal

alternative. In addition, the study concluded that the cost of addressing the impact of

waste disposal is tremendously high.


The other study developed simulation modeling to evaluate the cost efficiency of DW

management on the demolition project in Hong Kong (Lu, et al., 2009). This model

includes raw DW collecting and sorting, broken concrete sieving and stockpiling, steel

bar recycling, and waste disposal at the landfill. Whereas the time and cost parameters

of a given waste management method (selective demolition) were evaluated. Lu, et al.

(2009) reveal that the on-site DW management was operated smoothly and efficiently

with higher recovery rate for resources of different types. In addition, cost and time

can be reduced by doubling the resource provision on-site. In order to address the need

of sustainable development, a greater emphasis of cost efficiency is expected to be

placed on this topic in the future, due to the increasing need for sustainability

assessment that includes social, environmental and economic considerations.

2.6 URBAN REDEVELOPMENT DEMOLITION WASTE MANAGEMENT IN VIETNAM

2.6.1 Urban redevelopment in Vietnam

In the past 30 years, major cities in Vietnam have undergone tremendous population

growth and a rapid urban modernisation. In such cities, urban housing areas have high

population density, with more than 2,000 persons per one square kilometre. In

addition, the population of the city core is predicted to continue to increase and people

have started to express more concern about their quality of life. Whilst many

neighbourhoods were built around 30-40 years ago, which cannot satisfy the

requirements of natural disaster performance, as well as living conditions. As a result,

serious housing shortages and decay in the inner city have underpinned the need for

the city authorities to carry out large-scale redevelopment. In line with the economic

development and the high population density in Vietnam’s city cores, redevelopment

and new construction activities have become an essential part of contemporary urban

planning.

According to a report by the Ministry of Construction in Hanoi and Ho Chi Minh cities,

there were about 90% of low-rise blocks that were dilapidated, 25% of which were at

high risk to the residents (Bao Anh, 2011). Additionally, Hanoi is the second largest

city in Vietnam. According to the national census conducted in 2009, the

Hanoi’s population is estimated to be 6,451,909, with the average density of

approximately 1,979 people per km2. In addition, with the massive wave of immigrants

from other provinces flocking to Hanoi, the actual population in Hanoi is increasing at


an accelerated speed and this upward trend seems not to be going to cease in the

foreseeable future. Accordingly, the landscape in Hanoi city has gone through

spectacular changes. Despite the rapid urban development, there are about 1,500

dilapidated buildings in the old districts of Hanoi, mainly positioned in Ba Dinh, Dong

Da, Hoan Kiem, Hai Ba Trung, and Thanh Xuan districts, which are located in city

core (Figure 2-7).

According to the survey of Hanoi Construction Department, these old buildings were

built in the 1960s, 1970s and the later 1980s, with low-rise blocks from two to five

floors (Gia Huy, 2015). Constructed with out-dated technology, many of these earlier

buildings were improperly structured or environmentally obsolete, which not only

jeopardised the safety of residents, but also put the public’s safety at risk. Particularly,

the residents have refurbished through generations, which has, in part, accelerated the

deterioration. Moreover, the existing buildings are in possession of their own unique

characteristics, although such infrastructure did not meet the modern standards due to

a lack of community facilities. In addition, the old buildings aged about 50 years do

not have a private kitchen and toilets; especially the old neighbourhoods seem to be

overloaded because the density of residents has increased to almost twice, in

proportion to their initial capacity. A fact worth noting is that many old blocks have

sunk about 1.2 metres and could collapse at any time.

Figure 2-7: The aging blocks in Ba Dinh district, Hanoi


With the rapid deterioration rate and mounting public concern about living conditions,

in 2005, Hanoi Authorities announced a decree 07/2005/NQ-HĐND on urban

redevelopment, stating that the high-risk buildings should be the top priority. In 2008,

The Hanoi Authorities continuously issued a program 06 of urban redevelopment to

motivate the improvement of the dilapidated buildings by replacing complex buildings

with high-rise flats, commercial buildings, and green public spaces. However, in spite

of the city’s attempts, the pace of urban redevelopment after 10 years has been

comparatively low. To date, only 14 old blocks, located in the wards of Thanh Cong,

Kim Lien, and Giang Vo, have been redeveloped, accounting for 1% of buildings that

are labeled as those that need to be redeveloped in Hanoi City. If the urban

redevelopment pace remains static as of now, it might take about 100 years or more to

replace all the old buildings in Hanoi.

According to Ho Chi Minh City Construction Department, there are 474 dilapidated

buildings with 27,208 units, which were constructed before 1975 (Dieu, 2017). It is

estimated that 55% of those aging buildings that need to be redeveloped are at the

highest risk level (Figure 2-8). Similarly, Ho Chi Minh City has similar low pace to

Hanoi in implementing urban redevelopment.

Figure 2-8: The aging buildings in District 10, Ho Chi Minh City


Likewise, in Hai Phong City, there are marginally over 200 dilapidated buildings with

about 8000 inhabitants (Do, 2017). These buildings were built in the 1970s, which put

the residents at high risk (Figure 2-9). In 2017, Hai Phong issued an urban

redevelopment plan to construct new high-rise buildings in the next five years.

Urban redevelopment and housing problems in the city core have emerged as such

major challenges regarding to long-term economic, national security and societal

damage. The Government has announced that the aging buildings in the city core

should be demolished rather than refurbished. The earliest attempt of urban

redevelopment was in 2007 when the Vietnamese government enacted Decree

34/2007/NQ-CP on an urban renewal program focusing on the redevelopment of aging

buildings located within inner city areas. However, starting in 2007, the urban

redevelopment projects have been implemented at a low level across Vietnam for a

number of reasons pertaining to economic, social and environmental aspects. In fact,

the policy makers, planners, and contractors of this program have focused on technical,

land-use, and economic aspects to avoid social and environmental impacts.

Figure 2-9: Aging building in Le Chan district, Hai Phong

As discussed above, a large number of aging buildings in some main cities in Vietnam

have reached the end of their life span and are targets for demolition and

redevelopment. Accordingly, the Vietnamese government has announced the Decree

101/2015/NĐ-CP on the redevelopment of aging buildings, which are likely to be


dilapidated based on Vietnam housing law of 2014. The redevelopment project is

supposed to be undertaken on a large scale, not dealing with single dilapidated

buildings. Consequently, the demand of urban redevelopment leads to massive DW

generation, which can be a huge challenge to sustainable development in many cities

in Vietnam.

2.6.2 Demolition waste management in Vietnamese urban redevelopment projects

According to the national environmental reports, the amount of solid waste generated

in the country was 28 million tons in 2008, of which urban solid waste accounted for

46%, solid waste from industrial activities accounted for 17%, and the rest was solid

waste from construction, craft villages, health and rural activities (MONRE, 2011). It

is estimated that in Hanoi and Ho Chi Minh cities, about 1,000 to 2,000 tonnes of the

C&D waste have been landfilled daily.

The DW is normally dealt with in individual redevelopment sites, which is claimed to

be ineffective and insecure without technical and financial resources. Whilst DW in

many of the developed countries is managed properly with high levels of recovery

(Leigh & Patterson, 2006), there is no coherent framework for DW management in

Vietnam. According to the National report (2011), C&D waste is most often disposed

of in the nearest available open spaces or landfills either legally or illegally. These

seemingly distant threats can metastasise into immediate problems, leading to growing

public concerns about the impacts on the ecology, cityscapes and people’s health, such

as resource degradation, environmental pollution, and land value reduction. In

addition, the open space and landfill are overflowing rapidly to the extent that there

may be inadequate space for waste disposal, demanding a set of actions and strategies

for reduction, reuse, and recycling to remedy the environmental impacts and conserve

natural resources for the future.

According to the Vietnamese Ministry of Construction, in Hanoi City, over 1.7 million

square metres of aging buildings built from the 1960s to 1980s are being planned for

redevelopment, which is expected to produce a huge amount of DW (Gia Huy, 2015).

The redevelopment progress in Hanoi and other cities in Vietnam is behind schedule

because of the conflicts of economic, social and environmental objectives, ranging

from the issues of relocation, the cost of project implementation to the struggle with

environmental problems. The challenges facing the government are how to effectively


manage the volume of DW in the absence of a comprehensive framework that can

minimise the time and cost of DW management and its environmental impacts. In

addition, the duties and responsibilities of all stakeholders involved in the demolition

process are not clearly assigned. In fact, redeveloping the aging and dilapidated

buildings in Hanoi has garnered less attention from developers because it is very time-

consuming and costly. There is the need of improving the DW management

performance in Vietnamese urban redevelopment projects. At present, implementing

urban redevelopment DW management, Vietnam is confronted with four major

obstacles, including insufficient regulations, unavailability of data, absence of a

comprehensive framework, and low of environmental awareness.

‐ Insufficient regulation:

Recently, the Vietnamese government has increasingly promoted sustainable

development in the construction industry in which sustainability should be considered

when planning and executing construction projects (Huy, 2015). However, urban

redevelopment projects in Vietnam have been under scrutiny for failing to achieve the

environmental objectives, including poor DW management (Nguyen, 2015).

Currently, urban redevelopment policy in Vietnam has not provided a roadmap for

sustainable urban redevelopment. In addition, both of its generation and treatment

solutions are not taken into consideration, and there is an increasing concern about the

volume of waste generated by the redevelopment program and the consequences of

waste disposal. Therefore, there is a need for a comprehensive approach in the research

of DW management in Vietnam.

Integrated DW management is considered a feasible solution in order to reduce DW,

to maximise the reuse and recycling and proper disposal of DW. However, there is a

lack of tools to enable the communications of all stakeholders and support decision-

making regarding DW management in urban redevelopment projects at the district

level, offering decision makers a concise view of the critical challenges with a broader

and longer-term perspective. In fact, low tipping fees at landfills and illegal disposal

have suppressed interest in recovering DW in urban redevelopment projects.

Therefore, constructors have mainly focused on building demolition with little

attention to waste minimisation.


There is minimal regulation supporting DW management in the construction industry

in Vietnam, especially in urban redevelopment projects. In fact, DW management is

regulated jointly with municipal waste and most of the measures are aimed at the

improvement of municipal waste management. For example, The Vietnamese

Environmental Law is mainly concentrated on municipal solid waste management and

provides little environment-related legislative and policy framework for C&D waste

management.

‐ Unavailability of data

Obtaining reliable data on waste from the construction industry in Vietnam is not easy,

as data in this field is often managed together with the municipal waste one. This

makes it difficult to precisely estimate the amount of DW in urban redevelopment

projects. Whereas, the information of the DW, such as the amount of waste, the waste

compositions, and the rate of reusable and recycling waste, is essential for planning

and making decisions that support effective management.

‐ Absence of comprehensive framework:

A comprehensive framework and plans are essential; however, urban redevelopment

projects still lack clear guidance as to how to manage DW effectively. There is a need

of framework development to guide waste classification, reduction, reuse, recycling

and disposal of DW.

‐ Lack of environmental awareness:

Although sustainability is perceived widely in Vietnam, stakeholders have still

considered environmental issues as a low priority, especially DW management. In

addition, the practice of DW management and the adaptation of sustainable urban

redevelopment in Vietnam are still at a lower level compared to regional and

developed countries. This is because a DW management process is costly and time-

consuming for them to carry on in practice. Therefore, improving DW management

process can bring about a significant change to stakeholders’ awareness of

environmental protection in urban redevelopment projects.

In line with the need for effective urban redevelopment in Vietnam as stated in the

Decree 101/2015/NĐ-CP, the improvement of DW management should be considered

by addressing the obstacles faced in implementing DW management in Vietnam. This

study, therefore, aims to identify the key decision-making factors that influence DW


management in urban redevelopment projects in Vietnam. The GIS-based model is

applied to develop the database of DW. Subsequently, a decision-making framework

is proposed in order to improve DW management in Vietnamese urban redevelopment

projects. This framework may apply to other developing countries, which have similar

circumstances in urban redevelopment, such as China, Brazil, and India.

2.7 RESEARCH GAP

As discussed above, DW management has captured much attention over the last two

decades, focusing on five main areas: (1) strategy and solution, (2) decision support,

(3) environmental challenges, (4) stakeholder engagement, and (5) evaluation. This

has enriched the body of knowledge of DW management, as well as presented the

current status quo of DW management practices throughout the world. However, the

review indicates that knowledge and experience of DW management in an urban

redevelopment context is limited. Accordingly, research gaps can be identified and are

discussed as follows.

According to Roussat, et al. (2009b), effective DW management requires an integrated

stakeholder approach to include all the stakeholders involved in the demolition

process. However, stakeholder involvement has been limited to date because of cost

and time constraints (Lu, Lau, & Poon, 2009). It is, therefore, indispensable to consider

how communication and information exchange between different stakeholders can be

improved. In addition, there is urgency for a focus on the practice guidelines of

stakeholders’ responsibility in DW management in order to encourage improved

stakeholder buy-in and involvement.

There are a number of computer-based solutions, such as Building Information

Modeling (BIM) and Geographic Information Systems (GIS) that can support

decision-making; from the design to construction or building demolition stages. These

solutions offer useful and versatile tools for academics and professionals in

understanding the characteristics and amounts of waste in order to devise

comprehensive waste handling plans and strategies (Harrison et al., 2001; Najm & El-

Fadel, 2004; Sumathi, Natesan, & Sarkar, 2008). However, there is still a lack of

accurate construction waste data, especially in developing countries (Wu, et al., 2014).

This may be due to the fact that the focus of previous research on both C&D waste has

led to a gap in the understanding of DW, particularly that of urban redevelopment


projects. Therefore, further studies are needed about the impact of a wide range of

information technology systems on the management of DW in urban redevelopment

projects at the regional level.

Furthermore, there is a multitude of challenges in urban redevelopment DW

management due to the complexities involved, such as poor waste management

planning, the overlapping of responsibilities and ineffective time and cost management

(Lu, Lau, & Poon, 2009; Wu, Yu, Shen, & Liu, 2014). Therefore, effective waste

management requires a clear decision-making process with the inclusion of key

stakeholders, which involves project performances towards sustainability covering

different aspects such as economic, environmental, social, technical and institutional

ones. Therefore, more research needs to be conducted to investigate the important

factors influencing effective urban redevelopment DW management and to develop a

framework for improving DW management process, particularly in the context of

Vietnamese urban redevelopment.

Existing academic research underscores the integration of sustainability and DW

management, waste minimisation, environmental issues, waste estimation, and

evaluation. In recognition of those contributions to the knowledge of urban

redevelopment DW management, it should be noted that knowledge and experience of

DW management in an urban redevelopment context is limited. It is also discerned

that less attention has been given to the identification of important decision-making

factors influencing DW management in urban redevelopment projects. There is a

potential for developing knowledge in these areas further, particularly in consideration

of the complexities and challenges involved in delivering urban redevelopment

projects in Vietnam. The knowledge, insights and recommendations provided,

establish a theory framework that can critically address the issues associated with

urban redevelopment DW management to further promote sustainable urban

redevelopment. This framework will be applied in the investigation of the important

decision-making factors in the context of Vietnamese urban redevelopment DW

management. The following section presents the background of decision-making that

applies in the urban redevelopment DW management process.


2.8 RESEARCH CONCEPTUAL FRAMEWORK

2.8.1 Organisational decision-making

Decision-making has become one of the most active strategies in the management

research field (Papadakis, Lioukas, & Chambers, 1998). Decision-making is a process

whereby people gather information, propose and assess alternative resolutions, and

implement those decisions that influence their lives (Hain, 1980). Decision-making is

a process that is implemented over a period of time (Cooke & Slack, 1991) and is the

responsibility of key managers (Elbanna, 2006). This process reflects the interaction

between an organisation and its environment, which is embedded in both the internal

context and external context of the organisation (as cited in Elbanna, 2006). The

decision-making process combines certain steps in the particular order of identifying

existing problems, interpreting and diagnosing those problems and determining the

appropriate solutions (Cooke & Slack, 1991).

Papadakis, et al. (1998) indicate that a decision-making process is multidimensional

in nature and must be integrated over at least four basic perceptions: individual

decision opinion, strategic or management option, environmental determinism, firm

characteristics, and resource availability perception. Many studies have argued that a

decision that is categorised and labeled in the early stages of the decision-making

process can strongly impact the organisation’s subsequent response (Dutton, 1993;

Fredrickson, 1985). Papadakis, et al. (1998) state that the role of decision makers is

vital in determining the strategy content and process. However, their influences on the

decision-making process need to further underline the characteristics that are

important.

Regarding environmental determinism, the decision-making process is presenting the

adaptation to opportunities, threats, constraints and other environmental aspects

(Papadakis, et al., 1998). This adaptation is facilitated by top decision makers, and

answers the question of how environmental factors affect the decision-making process.

The research by Papadakis, et al. (1998) also indicates that the perspective of firm

characteristics and resource availability emphasises internal factors, such as internal

system, organisation performance, size and corporate control and also relates to

profitability and slack resources.


Elbanna (2006) concludes that both academia and executives have paid increased

attention to strategic decision-making, which are grouped into two categories, namely

content research and process research. Content research addresses the issues of the

strategy content such as portfolio management, diversification, mergers and the

alignment of organisational strategies with its environmental features. Meanwhile,

research tackled with the process in which a decision is made and carried out, followed

by figuring out and dealing with the resulting factors. It is noteworthy that these two

categories are not alternative choices (Mintzberg & Waters, 1985).

However, in comparison with content issues, process research has received less

attention from researchers (as cited in Elbanna, 2006). Many studies have advocated

integrating various perspectives of the decision-making process to develop strategic

decision-making process (Bryson & Bromiley, 1993; Chan, Scott, & Chan, 2004;

Elbanna, 2006; Lu & Yuan, 2010). It is of significance to combine the different

elements of decision-making, which would provide a better understanding of the

decision-making process (Hitt & Tyler, 1991).

In the field of waste management, the model of a decision-making process for

municipal solid waste management (MSWM) has integrated factors from various

aspects, such as economic, environmental and technical (Hung, Ma, & Yang, 2007).

The study by Hung, et al. (2007) also indicates that in recent years, sustainability has

been integrated into the models of MSWM. Morrissey and Browne (2004) suggest that

a sustainable decision-making model of MSWM should consider the environmental

effects, the consequences on the economy, and social acceptance.

Furthermore, Wilson (2001) proposes that combining different public groups’

perspectives in the early stages of the decision-making process is to find a

compromised solution. The novel sustainable decision-making model for MSWM is

proposed by Hung, et al. (2007), as shown in Figure 2-10. This model presents various

steps to develop the decision-making process for MSWM. Firstly, there is the

consideration of numerous contributing factors with respect to aspects of

environmental, economic, social, and so forth. Multiple stakeholders’ criteria are also

identified. Secondly, there are a number of methods of waste management that can be

used to prioritise alternatives.

As the waste management decision-making process involves different stakeholders

with different perspectives, it is essential to perform in-depth analysis to select the


viable alternative. The analyses are conducted on the basis of five steps of constructing

the hierarchical structure of waste problems, calculating the criteria weights,

determining the performance of the alternatives for each factor, aggregating the fuzzy

performance and rating the score of the alternatives. In addition, measuring the

agreement between stakeholders regarding the alternatives is needed. Finally, decision

makers can make decisions on waste management based on not only the compromise

solution, but also on the stakeholders’ agreement over all alternatives. This approach

can help decision makers avoid the likely conflicts in making decisions.

Figure 2-10: Steps of a sustainable decision-making model for waste management.

Adapted from ‘A novel sustainable decision-making model for municipal solid waste management’ by (Hung, et al., 2007), page 213.


In line with the study by Hung, et al. (2007), Mayer, van Bueren, Bots, van der Voort,

and Seijdel (2005) integrate the ‘sustainability’ element in the decision-making

process of urban renewal projects by addressing the complexity of perspectives from

various stakeholders. There is the need of collaboration in planning and decision-

making among different stakeholders in order to ensure that all stakeholders’

perspectives are included in the decision-making process. In addition, Mayer, et al.

(2005) also state that the decision support system (DSS) would facilitate sharing of

knowledge and information concerning the project between decision-makers. This

indicates that in sustainable urban redevelopment projects, stakeholders from different

areas, such as construction contractors, waste management contractors, planners, and

policy makers, must be able to communicate and share information effectively. Mayer,

et al. (2005) (Page 406) conclude that there is a need of methodologies and tools to

implement sustainable urban renewal projects, which ‘are able to support the

substantive (that is, content), as well as the political (that is, the context), dimensions

of decision-making’.

In addition, more recently, integrated assessment is more concerned with the

dimensions of the decision-making process and the use of participatory tools for both

environmental issues and other socio-technological systems (Ravetz, 2000; Rotmans,

van Asselt, & Vellinga, 2000). Besides the application of the decision-making theory

into urban redevelopment DW management, it is vital to integrate and to incorporate

sustainability in the decision-making process. As DW management in urban

redevelopment projects is complex, a compromising approach can facilitate the

confrontation of DW management issues among the stakeholders.

2.8.2 Research factors influencing demolition waste management in urban

redevelopment projects

Strategic decision-making plays a significant role in the field of management. Using

multi-criterion analysis is supportive for decision makers to make decisions in the

management process (Yau & Ling Chan, 2008). According to Walker (2015),

considerations that should be taken into account in the early stage of a construction

project are political, legal, economic, institutional, sociological and technical aspects.

Ng, Cook, and Chui (2001) add that the key issues of an urban regeneration project

planning are the project’s impacts on the society, economy, environment, and traffic.

In urban redevelopment projects, DW management encompasses environmental and


socio-economic issues and involves different stakeholders, which makes the

management process more complicated (Yau & Ling Chan, 2008). In order to achieve

integrated DW management, the contributory factors of the decision-making process

need to be fully perceived.

In fact, based on the three pillars of sustainability, scholars have different views

regarding which factors should be examined in the decision-making process. Research

by Yau and Ling Chan (2008) concludes that a sustainable urban regeneration plan is

demanded to mitigate the social impacts, enhance the economic targets, and take

environmental issues into account. Kum et al. (2005) give a simple decision-making

process for integrated waste management that influences can be categorised into seven

factors, including political, legal, technical, social, environmental and economic

factors, and available resources. Zhang and Li (2012) point out that the consideration

of sustainable construction waste management should be based on the evaluation of

sustainable attributes that can balance the environmental, economic and social

objectives. Therefore, assessing the environmental impacts of specific waste

management approaches, evaluating the cost of dealing with construction waste and

identifying social impacts can be factors that influence the decision-making process.

In this study, considering DW management at the district level, the DW issue is

complex and dependent on various factors specific to the region. Therefore, it is crucial

to analyse the information related to integrated DW management thoroughly to help

decision makers make the right decisions. Due to the growing complexity of the urban

redevelopment projects, the technical and institutional aspects are considered in order

to ensure the appropriate allocation of stakeholders’ responsibility and availability of

technical information. In addition, the performance metrics of DW management

should be in line with the three pillars of sustainable urban redevelopment including

economic, social, and environmental considerations.

Therefore, in this study, the decision-making factors which influence DW management

were encompassed under technical, environmental, social, economic and institutional

goals that can be achieved through integrated DW management in sustainable urban

redevelopment. Based on the analysis of related literature, the decision-making factors

are grouped under five categories including technical, environmental, economic,

economic, social and institutional. Table 2-2 shows the details of references to

literature from which potential factors have been developed. As a result, fifty-three


potential factors were obtained from the comprehensive literature review. These

factors were analysed and classified into 19 main themes, which represent the five

categories of DW management performance. This finding formed the main basis for

the questionnaire design used in the survey study.

Table 2-2: Research factors influencing DW management in urban redevelopment project

Category Theme Relevant literature

Technical (1) Demolition techniques

Poon, et al. (2001), Poon, et al. (2004), Lombardi, et al. (2011), Lu and Yuan (2010), Petersen (2004), Roussat, et al. (2009b), Lombardi, et al. (2011)

(2) DW management processes

Poon, et al. (2001), Poon, et al. (2004), Ding and Xiao (2014) Blengini (2009), del Río Merino, et al. (2009), Lu (2014), Seo and Hwang (1999), Qualharini and Flemming (2009), Marrero, et al. (2011)

(3) ICT-based solutions

Huuhka and Lahdensivu (2014), Kleemann, et al. (2014), Al-Saggaf and Jrade (2015)

(4) Time and risk management

Roussat, et al. (2009b), Chan, et al. (2004), , Akintoye and MacLeod (1997)

(5) Life cycle assessment

Blengini (2009)

Environmental (1) Stakeholder awareness

Rao and Zhang (2015), (Yuan, et al., 2011), Poon (1997)

(2) Environmental issues

Huuhka and Lahdensivu (2014), Yuan & Shen (2011), del Río Merino, et al. (2009), Blengini (2009), Marzouk and Azab (2014), Tam (2008) Marrero, et al. (2011)

(3) 3R strategies Poon, et al. (2001), (Yuan & Shen, 2011), del Río Merino, et al. (2009), Marrero, et al. (2011)

(4) Disposal control Poon (1997)

Economic (1) Cost-effectiveness Lu, et al. (2009), Yau and Ling Chan (2008), Vego, Kučar-Dragičević, and Koprivanac (2008), Mcdonald and Smithers (1998), Lu, et al. (2009), Roussat, et al. (2009b), Al-Saggaf and Jrade (2015)

(2) Recycled market Blengini (2009), Petersen (2004), Mcdonald and Smithers (1998), Roussat, et al. (2009b), del Río Merino, et al. (2009)

(3) Disposal costs Mcdonald and Smithers (1998), Roussat, et al. (2009b), del Río Merino, et al. (2009), Poon (1997)

Social (1) Community involvement

Zheng, et al. (2014), Bowie, et al. (2005)

(2) Safety implication Petersen (2004), Roussat, et al. (2009b), Yau and Ling Chan (2008)

(3) Preservation Yau and Ling Chan (2008), Zheng, et al. (2014), Petersen (2004), Lee and Chan (2008b)

(4) Job creation Roussat, et al. (2009b), Yau and Ling Chan (2008), Petersen (2004)

Institutional (1) Stakeholder engagement

Zheng, et al. (2014), Delmas and Toffel (2004), del Río Merino, et al. (2009), Marrero, et al. (2011), Lu and Yuan (2010), (Lam, Chan, Poon, Chau, & Chun, 2010), Liu, et al. (2005b), Roussat, et al. (2009b)


(2) Policy and guidelines

del Río Merino, et al. (2009), Rao and Zhang (2015), Marrero, et al. (2011), Bjerregaard (2008), Bjerregaard (2008), Poon (1997)

(3) Information and communication

Huuhka and Lahdensivu (2014), Kleemann, et al. (2014), Lombardi, et al. (2011), Chan, et al. (2004)

Based on the background literature covering C&D waste management, particularly

DW management in urban redevelopment projects, a conceptual framework for

improving DW management in urban redevelopment projects is developed, as shown

in Figure 2-11.

Figure 2-11: Conceptual framework of effective DW management in urban redevelopment projects

As illustrated in Figure 2-11, the research factors identified to influence DW

management in urban redevelopment projects are categorised as 1)Technical,

2)Environmental, 3)Economic, 4)Social, and 5)Institutional. These factors are

discussed as follows.

2.8.2.1 Technical factors

This category includes five main themes, covering 16 sub-factors that are summarised

from the relevant literature, namely demolition techniques, DW management

processes, ICT-based solutions, time and risk management, and life cycle assessment.

Influencing factors in urban redevelopment DW

management

Technical

Demolition techniques

DWM processes

ICT-Based solutions

Time & risk management

LCA

Environmental

Stakeholder awareness

Environmental issues

3R strategies

Disposal control

Economic

Cost -effectiveness

Recycled market

Disposal costs

Social

Community Involvement

Safety implication

Preservation

Job creation

Institutional

Stakeholder engagement

Policy guidelines

Information& Communication


The theme of demolition techniques refers to choosing the demolition method,

applying the selective demolition method, demolition skills and training, and

demolition equipment. According to Yau and Ling Chan (2008), an urban regeneration

project can be a source of conflict if it is poorly planned. In light of that, demolition

technique consideration should be taken into account so that demolition work can

facilitate the urban redevelopment DW management process. For example, Poon, et

al. (2004) state that choosing a proper demolition method can ease on-site waste

sorting and increase the waste recovery rate. In addition, the selective demolition

technique is adopted to dismantle the selected material in different demolition stages.

This method helps retrieve the recyclable and reusable waste in an easy and systematic

way (Poon, et al., 2004). In addition, the C&D waste generation is substantially

affected by how skilful construction workers are (Lu & Yuan, 2010). If workers are

incompetent, the implementation of the construction or demolition works will result in

large amount of waste (Wang, Kang, & Wing-Yan Tam, 2008). Therefore, ‘demolition

skill and training’ is considered an influencing factor in implementing waste

management in construction projects. Furthermore, the stakeholders may reluctant to

invest in demolition equipment, particularly low waste technology, which capital cost

may initially outweigh return on investment. This results in the difficulty in on-site

waste classification and low rate of waste recovery (Poon, et al., 2001).

A DW management process theme consists of DW management procedures, onsite-

waste sorting, waste estimation, planning of waste sorting space and landfills. These

are all important stages of the DW management process. For example, Roussat, et al.

(2009b) argue that a strategy of DW management could not be effective without an

appropriate classification of waste types that can be recovered for different purposes,

such as road engineering and concrete block production. Poon, et al. (2001) add that

effective waste management on the construction site usually involves scheduling for

waste clearance, waste collection, and waste disposal, which should be developed

before construction activities. According to Poon, et al. (2001) off-site waste

classification can be more cost-effective than that of on-site classification because it

does require less workers and less cost expenditure on a construction site. However,

from the perspective of environmental protection, off-site waste classification is not

recommended for C&D waste management. This is because the waste is more easily

classified directly from the source than that in case of mixing and then separating it.


Thus, the contractors can increase the value of recyclable waste and avoid the pollution

caused by mixed materials (Wu & Ann, 2014). In addition, Formoso, Soibelman, De

Cesare, and Isatto (2002) indicate that waste estimation, such as the amount of waste

and the waste components, provides stakeholders crucial information for achieving

cost and plan effectiveness in DW management.

ICT-based solutions denote the application of ICT-based in improving DW

management in urban redevelopment projects. There is an increasing trend of ICT-

based applications in the construction industry due to their various individual features

and capabilities (Al-Saggaf & Jrade, 2015). Recently, ICT-based solutions have been

applied in the field of waste management as a decision support tool (Al-Saggaf &

Jrade, 2015; Chalkias & Lasaridi, 2011). For example, Karadimas and Loumos (2008)

state that an integrated GIS-based model has been considered as one of the most

powerful platforms to computerise the process of waste planning and management.

The theme of time and risk management comprises the duration of demolition work

and identifying the risks associated with demolition work. The time factor is an

important concern that stakeholders need to consider prior to implementing DW

management. According to Poon, et al. (2001) and Lu, et al. (2009), stakeholders are

reluctant to conduct on-site sorting because of time constraints. Therefore, there is a

need for proper time management in DW management.

The theme of life cycle assessment refers to a methodology that emphasises the

evaluation of specific elements of a product system to investigate its environmental

impacts (De Benedetto & Klemeš, 2009). By this approach, Blengini (2009) states that

a comprehensive energetic and environmental picture regarding demolition and final

disposal of a building can be investigated. Accordingly, the recycling potential of DW

can be estimated. Thus, consideration of life cycle assessment should be a rudimentary

fundamental for sustainability.

2.8.2.2 Environmental factors

According to (del Río Merino, et al., 2009), all construction projects have impact on

the environment through the use of raw materials, energy consumption, and waste

generation. For example, the hazardous components of DW sent to landfill can pose a

potential risk to the groundwater by leaching chemical hazardous waste (Roussat, et

al., 2008). In addition, it is indisputable that the lack of full awareness of and

knowledge about demolition results in demolition failures (Liu, et al., 2005b).


Therefore, considering and understanding environmental factors in formulating plans

of DW management could diminish the environmental impacts. The environmental

category consists of four main themes covering 11 sub-factors, namely stakeholder

awareness, environmental issues, and 3R strategies.

The theme of stakeholder awareness refers to the willingness of DW management by

stakeholders, and training in integrated waste management. Insufficiency of interest

and understanding by stakeholders could hinder the improvement of DW management

in urban redevelopment projects. Meanwhile, the uniqueness of DW and hazardous

DW, emission of greenhouse gases, disposal control, environmentally could impact

the assessment of DW and cause the environmental problems associated with DW

management, which are grouped in the theme of environmental issues. The problems

associated with DW management include environmental impacts, low rate of recovery,

difficulties in waste sorting, and higher energy consumption for DW treatment.

Therefore, understanding DW’s uniqueness in the early stage of the demolition work

is vital for effective DW management. In addition, the hazardous waste, such as metal,

paints and bituminous, make up a significant component of DW. The audit of these

components should be done properly in demolition work. Construction activities, such

as manufacturing, transporting of materials, and disposal waste, can consume primary

energy, which results in a large amount of greenhouse gas emission (Yan, Shen, Fan,

Wang, & Zhang, 2010). Balancing greenhouse gas in construction projects,

particularly in the process of waste disposal, can reduce environmental impacts.

Furthermore, disposal control implies the consideration of disposal fee and landfill

sites in DW management. Hendriks and Jansen (2001) affirm that high disposal fees

of C&D waste should be imposed by the authorities and the construction industry that

may help raise stakeholders’ awareness of waste management.

The 3R strategies theme takes into consideration 3R promotion in DW management,

the use of recycled materials, and rate of waste recovery. These strategies should be

expedited in the process of choosing waste management measures (Peng, et al., 1997),

which could increase the waste recovery rate and remedy the environmental impacts

as well as soothing the pressure on the landfills.

2.8.2.3 Economic factors

The economic category is composed of eight factors under three main themes

regarding cost-effectiveness, recycled market, and disposal cost. The theme of cost-


effectiveness takes into consideration the cost of demolition, waste transport, and waste

treatment; the cost-effective demolition plan; and energy saving during DW

management process. From an economic viewpoint, ineffective urban redevelopment

DW management could result in tremendous losses in the process of waste treatment

and waste recycling. Therefore, cost-effective plans would assist stakeholders in saving

energy and the cost of DW management. It is of valuable to determine which economic

factor should be important to be considered. For example, it is crucial to identify the

demolition plan that can be implemented with reasonable efforts at an affordable cost

and involve the use of recycled materials. Accordingly, this can enhance the

stakeholders’ willingness to conduct the DW management or recycle DW.

Recycled market refers to the development of the recycled market in order to encourage

the use of recycled materials. The development of the recycling market is reckoned as

one of the effective strategies of C&D waste management (Wu & Ann, 2014).

Disposal cost signifies the issue of proposing an appropriate fee for DW disposal. del

Río Merino, et al. (2009) indicate that poor on-site waste sorting results in not only

extra waste processing but also higher disposal fees. The disposal fees should be

properly imposed for different types of DW.

2.8.2.4 Social factors

In order to achieve sustainable development through urban redevelopment projects, it

is also important to identify the social factors in the preparation for the DW

management plan. This category consists of nine sub-factors under four main themes:

community involvement, safety implication, preservation, and job creation.

The theme of community involvement takes into consideration the role, supportive

actions, monitoring and feedback by community, and public awareness of urban

redevelopment DW management. The theme of safety implication is divided into two

sub-factors, which are safety at work and the reduction of community disturbance.

Safety is an important aspect for society. Considering security at the workplace and

the reduction of environmental impacts on the community will ensure public health

and quality of life in urban redevelopment neighbourhoods. Preservation reflects the

conservation of natural resources, and historical structures and local cultures. It is

witnessed that heritage should be conserved properly for the enjoyment of society

through different generations (Fung, 2004). Job creation is one of the major indicators

of social sustainability (Omann & Spangenberg, 2002). In this sense, this study


considers job creation as the primary factor in urban redevelopment DW management.

This factor emphasises the number of jobs created due to DW management regarding

demolition work and waste processing.

2.8.2.5 Institutional factors

In order to ensure that the right decision can be made, the institutional factors that

contribute to effective DW management should be considered. This category includes

nine factors, which are grouped into three main themes: stakeholder engagement,

policy and guidelines, and information and communication.

Stakeholder engagement refers to the involvement of key stakeholders in DW

management, including the roles and responsibilities of stakeholders; control and

feedback by stakeholders; and stakeholders’ perspectives on the DW management

process. Identifying who needs to be specifically engaged in DW management process

is vital to making an effective DW management plan. The theme of policy and

guidelines embodies the development of the best practice guidelines for urban

redevelopment DW management and the accomplishment of policies and strategies

related to DW management in urban redevelopment projects. According to Lu and

Yuan (2010), stakeholders may be reluctant to implement C&D waste management in

their construction projects if there is a lack of guidelines and government’s

supervision. This results in poor DW management planning and the overlap of

stakeholders’ responsibilities. Specifically, (Lu & Yuan, 2010), a good policy system

is considered as the most important factor to the success of waste management in

construction projects in China (Lu & Yuan, 2010). Therefore, accomplishing policies

and strategies will help address the problems for implementing effective DW

management in urban redevelopment projects. ‘Information and communication’

reflects the reports or database in the urban redevelopment DW management process

which can help stakeholders design an effective waste management plan and avoid

miscommunication. Shen, et al. (2007) state that the more crucial information and

knowledge the stakeholders share, the better projects’ performance is. Thus, this factor

was identified as an important theme in improving DW management in urban



2.9 SUMMARY

Through the literature analysis, a holistic view of DW management in urban

redevelopment activities is examined. It is highlighted that urban redevelopment is an

inevitable stage of the modern urban development process. This is occurring in many

cities all over the world, especially in developing countries that are facing dilapidation

in the city core. However, as the urban redevelopment activities are increasing, DW

management is receiving less attention.

In Vietnam, there is a lack of regulation and information to assist stakeholders in

implementing effective urban redevelopment DW management. Therefore, it is crucial

to develop knowledge in these areas further, particularly in view of the complexities

and challenges involved in delivering urban redevelopment projects. The knowledge,

insights, and recommendations lend urgency for practitioners and academics to

construct a conceptual framework to critically address the issues associated with urban

redevelopment DW management, to further promote the sustainability of urban

redevelopment. This research provides a better understanding of the important

decision-making factors that influence the implementation of effective DW

management in Vietnamese urban redevelopment projects.

In order to establish a decision-making framework, a thorough and extensive

understanding of factors affecting the decision-making process of DW management is

investigated. A number of issues have been raised to identify the factors relevant to

the technical, economic, environmental, social, and institutional aspects.

Although the 53 decision-making factors under five categories in this study are

regarded as important influences in urban redevelopment DW management, people

may have different perceptions towards their relative importance. Wang and Yuan

(2011) argue that the perspectives of decision-making factors can be affected by

stakeholders’ experience, background, personal beliefs, and social culture. Hence, this

study aims to address the significant research gap by identifying the decision-making

factors based on the perspectives of different groups of stakeholders, academics,

planners, consultants, engineers and policy makers in the context of Vietnamese urban

redevelopment through questionnaire surveys and interviews. The research design is

presented in detail in the next chapter.

Chapter 3: Research Design 63

Chapter 3: Research Design

3.1 INTRODUCTION

A proper research design before embarking on research actions is necessary to

facilitate effective data collection and reliable results. The research design is a plan for

undertaking research in order to achieve the research questions and objectives by

adopting appropriate and feasible methods (Sproull, 2002). Fellow and Liu (2015)

state that choosing the research methods requires the logic and relationship between

data collection analysis and the research questions. This research adopted the research

strategy of social science.

This chapter first explores the research proposition and the philosophical basis of the

research methodology that is used in this study. It then presents the research design

with the explanation of the research approach and the selection of research methods

adopted in the study: questionnaire surveys, interviews, and a case study. This is

followed by the research process, including the three main stages. Four main

approaches in the research development stage were then discussed and finally, the

consideration of research ethics is drawn.

3.2 RESEARCH PROPOSITION

There are a variety of methods in designing a research plan in terms of data collection,

analysis and modelling. Underlying the weaknesses and strengths of various methods

can help select the most appropriate methods and tools for the research.

The intent of this study is to explore the factors affecting the decision-making process

and develop a decision support model for DW management in urban redevelopment

projects. In this study, several research methods are applied to answer the research

questions. As can be observed, the research proposition is drawn based on the research

questions, aim and objectives, which will stimulate new approaches to reach the aim

of the research (Figure 3-1).

64 Chapter 3: Research Design

3.3 RESEARCH PHILOSOPHY

Research philosophy has a significant influence on the link between the targeted set of

terms and concepts that define an academic discipline and its process (Johnson &

Clark, 2006). According to Fellows and Liu (2015), a research paradigm can be

considered from a theoretical framework perspective. This perspective represents how

a researcher views the world (Creswell, 2013). It is crucial to identify what views and

approaches are applied in developing a conceptual framework regarding the selected

topic (Fellows & Liu, 2015). The paradigm of the study should be established as the

set of concepts and beliefs upon which a scientific field can be understood. In addition,

according to Creswell (2013), the philosophical position need to be understood before

the design of the whole research. The study by Mark, Philip, and Adrian (2009)

Research questions 1. What are the key decision-making factors influencing demolition

waste management in Vietnamese urban redevelopment projects? 2. How do the key decision-making factors influence demolition waste

management in Vietnamese urban redevelopment projects? 3. What is the necessary information to support key stakeholders in

demolition waste management in Vietnamese urban redevelopment projects at the district level?

Research aim The aim of this research is to develop a comprehensive decision-making framework for improving demolition waste management in Vietnamese urban redevelopment projects at the district level.

Research objectives 1. To explore the current DW management in urban redevelopment

projects and in the context of Vietnam. 2. To identify critical decision-making factors of DW management in

urban redevelopment projects. 3. To develop a decision-making framework and critical supporting

information to assist decision makers in improving demolition waste management in Vietnamese urban redevelopment projects at the district level.

Figure 3-1: Research proposition


indicated that the research design decision should be developed based on the research

questions, objectives and research philosophy.

Creswell (2013) contended that there are four approaches in identifying the best

methods for research including postpositivism, constructivism, advocacy, and

pragmatism. The main elements of these philosophies are shown in Figure 3-2.

Figure 3-2: Philosophical Positions (Creswell, 2013)

Postpositivism is known as positivism or postpositivism research or empirical science.

This philosophy is an approach of natural sciences (Neuman, 2000). Fellows and Liu

(2015) claimed that postpositivism which is related to rationalism, empiricism and

objectivity represents a conventional research philosophy based on facts including

non-metaphysical and phenomena that can be observed. It is assumed that since

postpositivism fits quantitative research better than qualitative ones, this philosophy

is usualy applied in experiments, surveys and statistical analysis (Creswell, 2009).

Constructivism reflects an interpretive research approach in which the researcher uses

his or her individual experience to conceptualise facts and phenomena rather than the

researcher’s objective and observation (Creswell, 2009). According to Neuman


(2000), constructivism is ‘the systematic analysis of socially meaningful action

through the direct detailed observation of people in natural settings in order to arrive

at understandings and interpretations of how people create and maintain social worlds’.

This is particularly suitable for research that has a complexity of views and multiple

meanings. Fellows and Liu (2015) stated that constructivism is a typical approach to

qualitative analysis.

Advocacy is known as a participatory paradigm, in which research should be

integrated with politics and political agenda (Creswell, 2009). This can combine

various perspectives and the experiences of people from different backgrounds

(Morris, 2006). Advocacy research normally deals with the need of person or groups

of people that may be disenfranchised or trivialised. The type of research that applies

this approach is normally qualitative research.

Pragmatism is an approach that combines different methodologies to identify the

research problems resulting from consequences, circumstances and activities

(Creswell, 2009). Patton (2002) stated that the application of pragmatism research can

help identify the research problems and figure out the solutions. This approach support

research which uses mixture of methodologies and deals with not only qualitative but

also quantitative database that can help the researcher find the best answers to research

questions.

According to research’s concerns and objectives (as discussed in section 1.3 and 1.5,

Chapter 1), this study aims to explore and investigate the critical decision-making

factors that help improve the urban redevelopment DW management and then develop

a decision-making framework. Therefore, pragmatism is the most appropriate

approach for this research. Pragmatism adopts to mixed methods, different

assumptions, and various forms of data collection and analysis (Creswell, 2013). This

philosophy is possible in conducting a study with variations in epistemology and

ontology, to answer the research questions. This proves the legitimacy of mixed

methods in solely study, which has been widely applied in urban sustainability (van

Bueren & ten Heuvelhof, 2005; Williams & Dair, 2007).


In this research, the methods were adopted separately. The quantitative analysis was

first employed to deal with the questionnaire survey results. Then, the qualitative

analysis was used to improve the proposed framework based on the interview results.

A case study was conducted to develop a decision support system by using a GIS-

based solution. Finally, a comprehensive decision-making framework of urban

redevelopment DW management was finalised. The details of the research

methodology will be presented in the next sections.

3.4 RESEARCH DESIGN

According to Mark, et al. (2009), the research design is defined as an overall

framework aiming at answering the research question in sequence. This is developed

based on both research concept and research contribution. The research design

provides a scheme according to which the research can be conducted including data

collection and analysis so that all research questions are addressed (Bryman & Bell,

2015). Fellows and Liu (2015) state that consideration of the appropriate methods

needs to be logically linked with how the data can be analysed in order to answer

research questions and achieve research objectives.

3.4.1 Research approach

This research is designed as a pragmatist approach. This approach is credited for

bringing flexibility and simplicity to the research process. This involves different

methods in finding appropriate solutions to deal with the research questions. Specially,

the research approach discovers how to approach data collection and analysis to

develop or test the theory for a research (Mark, et al., 2009). This research combines

both inductive and deductive approaches at different steps of the research process.

While inductive research formulates a theory from different observations, deductive

research develops a theory aiming at a rigorous test (Yin, 2013).

The deductive approach is applied in identifying theoretical decision-making factors

of urban redevelopment DW management, which are extracted from the literature. In

addition, these theoretical factors are formulated in the process of analyses of

stakeholders’ perspectives to develop a decision-making framework, which is an

inductive approach in nature.


In this study, the research approach adopted both qualitative and quantitative methods

to address the research questions and seek to attain the research objectives. Once the

quantitative methods are employed, accordingly, data are collected and analysed in

numeric form (Fellows & Liu, 2015). At the same time, qualitative methods are

adopted based on the constructivist approach. Qualitative research can help identify

and understand the issues behind any phenomenon and can also provide intricate

details (Corbin, Strauss, & Strauss, 2014). This method is employed to analyse the data

from different sources, while seeking information regarding stakeholders’ perspectives

and identifying the action plans for improving the decision-making process. Thus,

interpreting the entire analysis requires a combination of both quantitative and

qualitative data.

In this study, the sequential strategy is employed the mixed methods design of

Creswell and Plano Clark (2011), which analyses both quantitative data and qualitative

data, in order to interpret the research problems. The mixed methods strategy is

adopted based on knowledge claims of the pragmatic paradigm. Creswell (2009) states

that the usage of both a quantitative and qualitative analysis can help the researcher

incorporate strategies of enquiry in collecting data.

The distinctions of the selection of quantitative, qualitative, or mixed methods are

described in Table 3-1. Gephart Jr (1991) adds that the analysis of quantitative and

qualitative data helps to provide a more complete picture of the phenomenon.

Therefore, by adopting the mixed methods, the researcher could gain insight into the

research problems and deal effectively with the research questions. Therefore, an in-

depth identification of the factors influencing the decision-making process is vital. The

use of quantitative methods to explore the stakeholders’ perspectives, identify critical

decision-making factors, and develop a supporting database is necessary. In addition,

the qualitative approach is adopted to elaborate and validate the results from the

quantitative process. Three main research methods were selected and are described in

the next section.


Table 3-1: Quantitative, qualitative, and mixed methods approach analyses by Creswell (2009)

Items Qualitative

Approach Quantitative

Approach Mixed-Method

Approach

Philosophical assumptions Strategies of

inquiry

Constructivist/ Advocacy Participatory Phenomenology,

grounded theory, ethnography, case study, and narrative

Post positivist Surveys and

experiments

Pragmatic Sequential,

concurrent and transformative

Data collection methods

Open-ended questions, emerging approaches, text or image data

Close-ended questions, predetermined approaches, numeric data

Both open- and close-ended questions

Data analysis strategies

Focus on a single concept or phenomenon Validate the

accuracy of research results Provide

explanations of the data Create a plan for

the changes or reform Interact with

participants

Verify theories Identify variables

data Link the variables

in questions Identify the

reliable and valid data Observe and

compute the data numerically Use unbiased

approaches Adopt statistical

procedures

Collect both quantitative and qualitative data Establish a

rationale for mixed data Incorporate the

data at different research stages Present visual

pictures of the research process Employ both

qualitative and quantitative analysis

3.4.2 Selection of research methods

As the research aim is to develop a decision-making framework in improving DW

management in urban redevelopment projects, this requires a mixed method of both

qualitative and quantitative approaches to collect and analyse data to identify the

important factors influencing DW management. In addition, in the decision-making

process, a decision support system based on GIS tools is proposed to provide a

supporting database. Qualitative and quantitative approaches can be combined in


different forms according to varied research targets. The research questions are solved

by integrating quantitative and qualitative methodologies, selecting appropriate

research methods, and formalising a logical research process. Four main research

methods are adopted in this study, including literature reviews, questionnaire surveys,

interviews, and case studies. The key features and objectives of each method are

described in Table 3-2.

Table 3-2: Summary of selection of research methods

Methods Key features Objectives

Questionnaire survey

Allowing an approach to a large survey sample. Allowing quantitative

analysis of a large number of variables Not restricted to the physical

locations of the participants.

Identifying the important factors influencing the decision-making process in improving urban redevelopment DW management. Analysing statistically the participants’

responses. Investigating a consensus among five

stakeholder groups in determining critical factors. Revising the conceptual framework of the

decision-making process.

Interview Allowing an investigation directly on critical factors. Allowing a discussion on

action plans in improving DW management in urban redevelopment projects. Allowing a validation of the

proposed decision-making framework.

Gaining in-depth practice opinions corresponding to each critical factor. Validating the proposed framework of

decision-making process. Developing action plans in improving DW

management in urban redevelopment projects.

Case study Allowing a development of supporting database. Allowing an application of

GIS-based in assisting the decision-making process

Developing a supporting database in making decision of DW management in urban redevelopment projects. Applying the GIS-based model as a

decision support tool to practically develop the database.

Literature needs to be reviewed in order to identify the global trend of urban

redevelopment; the need of DW management in urban redevelopment projects;

research problem; and the context of urban redevelopment DW management in

Vietnam. Based on the literature review, the conceptual decision-making framework

for improving DW management in urban redevelopment projects is proposed, which

includes 53 identified factors that influence the decision-making process. The analyses


of quantitative data and qualitative data can aid the interpretation for revising and

validating the conceptual decision-making framework.

A quantitative survey is an appropriate approach for understanding the stakeholders’

perspective and their consensus about critical decision-making factors, while a

qualitative approach for the interview is appropriate to elaborate and validate the

proposed decision-making framework from the survey result. In addition, the action

plans for improving DW management in urban redevelopment projects are finalised

by qualitative analysis. A case study is used for developing a supporting database by

the GIS-based tool. These selected methods are systemised into three research stages

in the research process, which will be presented in the next section.

3.5 RESEARCH PROCESS

The research process is designed to consist of three stages. It includes establishing the

conceptual framework, developing framework, and developing supporting database.

Research methodologies were consequently designed to adopt data collection and data

analysis as shown in Figure 3-3.

3.5.1 Establishing conceptual framework

The research begins with the initial stage of ‘establishing conceptual framework’, in

order to explore the conceptual framework for the study. The research problem was

first explored before research questions and objectives were identified. The relevant

theories, the context of study in Vietnam, and existing research of DW management

in urban redevelopment projects were then reviewed. The review of literature helped

identify the research gaps and factors influencing the DW management decision-

making in urban redevelopment projects. Based on the analysis of factors influencing

the decision-making process, the conceptual framework was proposed, then revised

and validated in the survey and interview studies in the next stage.

3.5.2 Development of the framework

In stage 2, the conceptual framework was developed through the questionnaire survey

and interview processes. The questionnaires were first clarified and amended in the

pilot study before the survey was conducted. Data collected from the survey were

analysed with SPSS in order to explore the perspectives and consensus of key

stakeholders who are involved in DW management in urban redevelopment projects.


Based on the results of the quantitative analysis, the critical factors were identified in

helping revise the conceptual framework. The semi-structured interviews were then

conducted with a strong focus on an in-depth investigation into the important impact

of critical factors. The qualitative data were analysed in order to validate the proposed

framework and synthesise the action plans that improve DW management in urban

redevelopment projects. In this stage, it also identified the critical factors through

Interview

Figure 3-3: Research process

Pilot study Questionnaire clarity and comprehensive

Investigate in depth critical factors

Stage 2: Development of framework

Questionnaire survey

Survey Structured questionnaire

Quantitative data analysis by SPSS

Revised decision-making framework

Qualitative content analysis

Decision-making framework validation

Action plans

Stage 3: Development of supporting database Urban redevelopment projects information C

ase stud

y Decision-making framework finalisation

Preparation of DW database

Developing GIS-Based model for supporting

d b

Stage 1: Establishing conceptual framework

Literature review Urban redevelopment DW management Study context in Vietnam Decision-making

Identify research problem and research gap

Establish research questions and objectives

Identify factors influencing decision-making process

Conceptual decision-making framework


interview study, which were analysed to develop critical supporting database in GIS-

based model in the next stage.

3.5.3 Development of supporting database

In the last stage, the critical supporting database was developed to facilitate the

decision-making process of DW management in urban redevelopment projects. A case

study comprises four real urban redevelopment projects in Ba Dinh district, Hanoi,

Vietnam, which were chosen to practically develop database of DW management in

the form of GIS-based model. The spatial and attribute data were collected regarding

the amount and components of DW, the locations of buildings and projects, and the

information of landfills. This database was integrated with critical decision-making

factors to establish decision-making framework for improving DW management in

Vietnamese urban redevelopment projects at district level.

3.6 RESEARCH METHODS

This research was developed as described above and conceptualised in Figure 3-4.

Four main research methods were adopted to conduct research into background

investigation, data collection, and data analysis. These include literature review, the

questionnaire survey, the interviews, and the case study. The research findings were

investigated based on the analysis of quantitative and qualitative data. The research

methodologies will be discussed in the following sections.

3.6.1 Literature review

Literature review plays a vital role in a study, helping the researcher highlight the

research problems and identify research gaps. According to Cavana, Delahaye, and

Sekaran (2001), ignoring both important and unimportant variables in the research

backgrounds may have negative influence on the validity and reliability of the findings

and research significance. In part, the literature review aimed to establish the research

background (McMurray, 2004).

As a consequence, the background knowledge could provide the rationale to set the

research questions and research objectives. The relevant knowledge is conceptualised

for further investigation in addressing the research questions. All the relevant

knowledge helps to develop the conceptual framework and justify the questionnaire

survey.


This research began with an extensive review of books, professional journals,

conference papers, government documents, internet resources, and so forth in the

global context as well as in the Vietnamese context. The knowledge relating to urban

redevelopment, DW management, sustainability, green construction, integrated waste

management, and decision-making theory was captured. Based on the review, the

concept of sustainability was explored to integrate in DW management, in order to

achieve sustainable urban redevelopment. Therefore, different aspects of sustainability

were analysed and integrated in exploring decision-making factors of DW

management in urban redevelopment projects, such as economic, environmental,

social, technical, and institutional.

In addition, a critical review was undertaken, focusing on the existing research

regarding DW management in urban redevelopment projects in order to identify the

research trends and research gaps. The research by Poon (1997) is reckoned as the

early research related to DW management in urban redevelopment in Hong Kong.

Based on that, the literature from 1997 to 2016 was therefore reviewed with reference

to research concerning the DW management of urban redevelopment projects.

All the 204 articles were analysed according to the year of publication, publication

outputs of country/region, distribution of outputs in journals and subject categories.

The publications from a range of leading journals were identified and used to explore

research trends. The results indicate that knowledge and experience of DW

management in urban redevelopment projects are limited. Hong Kong, the United

States, and United Kingdom are key contributors, while countries such as China, India

and Brazil are relatively less represented. Waste Management; Resources,

Conservation & Recycling; Building Research & Information; and Waste Management

& Research are identified as active journals in publishing DW management research.

The scope of this review identifies key knowledge gaps in current research and offers

recommendations for future research. The background literature and the context of

DW management in Vietnam were reviewed to synthesise the factors affecting DW

management in urban redevelopment projects, which established a conceptual

framework. The conceptual framework included 19 main themes covering five

categories: technical, environmental, economic, social, and institutional. These main

themes formed the main basis of the questionnaire design, which resulted in 53 factors

in the survey study.


3.6.2 Questionnaire survey

The questionnaire survey aimed at identifying which decision-making factors are

significantly concerned by stakeholders when they make decisions about DW

management in the context of urban redevelopment projects. The results of the

questionnaire survey helped to achieve the second research objective and generate data

which enable further analysis in the interview study. The questionnaire survey was

suitable for this study because it collects data from a large range of industry

perspectives. In addition, the respondents provided a ranking of the extent to which

the decision-making factors influence DW management in urban redevelopment

projects.

The questionnaires used in the survey contained, multiple choice questions, single-

choice questions, scale questions using a Likert scale, and open questions. After the

questionnaires were developed, a pilot test was conducted to evaluate the survey

procedures and to modify its contents, after which the questionnaires were altered for

the better. The main questionnaire included 53 influencing factors that were considered

to be in five categories, which were applicable to DW management in urban


In the questionnaire survey, the survey samples were comprised of selected industry

practitioners and advisors in the field of DW management in Vietnamese urban

redevelopment projects, which were categorised in five groups. Firstly, academics

include experts who are working in the universities and research institutes advising the

development of C&D waste policy. Secondly, planners include people working in

government agencies and local authorities involving in the DW management planning

in urban redevelopment projects. Thirdly, consultants are defined as industry

practitioners, including private companies, advising on environmental considerations

of urban redevelopment DW management.

Engineers were selected from both civil construction and environmental disciplines in

construction and waste management contractor organisations. These organisations are

responsible for demolishing process, on-site waste classification, waste collection,

waste transport, and waste disposal. Finally, policy makers are defined as public sector


experts who directly involved in the development and implementation of the decision-

making process, policy and guidance of urban redevelopment DW management.

The questionnaires were sent to 500 respondents selected from five key stakeholder

groups who play a critical role in DW management in Vietnamese urban

redevelopment projects. However, only the respondents who were interested in this

survey and fulfilled the sample questionnaire were eligible for the research. The

respondents were provided with self-administered questionnaires and were asked to

rate, on a five-point Likert scale ranging from 1 = Not at all important to 5 = Extremely

important, to what extent the decision-making factors affected DW management in

urban redevelopment projects.

The data collected from the questionnaire survey was coded before the quantitative

analysis in Statistical Package for Social Science (SPSS) for Windows version 23. In

order to determine how many factors significantly influence urban redevelopment DW

management, six main tests were conducted to identify the critical factors. These

critical factors were then prepared for in-depth interviews. The purposes and results of

statistical analyses using SPSS (Statistical Analysis Package) are presented in Table

3-3.

The normality test was first conducted to find out the differences of the five groups’

stakeholder perspectives for all 53 factors. According to Field (2014), the difference

is calculated by deducting the scores of variables. The outcomes from the normality

test presented that the distributions of all the differences of 53 factors were

significantly non-normal with p<0.01 (Appendix B1). The non-parametric tests,

therefore, are required to compare the five groups of stakeholders’ perspectives in

ranking 53 research factors. The non-parametric Kruskal-Wallis test is used to

compare three or more independent samples and Post-hoch analyses of statistically

significant comparisons were used with multiple Mann-Whitney U tests to compare

two independent samples (Field, 2014).

Table 3-3: Methods of statistical analysis

No. Purpose Test Outcomes


1 ‐ Test the internal consistency of the scale

Cronbach’s alpha

‐ Data reliability

2

‐ Identify the most influenced decision-making factors of demolition waste management

Descriptive statics (mean and standard deviation)

‐ Respondents’ profile ‐ Different stakeholders’ perspectives on the critical decision-making factors ‐ Critical factors of decision-making for demolition waste management

3

‐ Determine the differences among the critical decision-making factors

Kendall’s coefficient of concordance (W)

‐ The differences in perceptions on the relative influence of decision-making factors’ rank among respondents

4

‐ Determine the statistically the significant divergences in the mean ranks of critical factors

Non-parametric Kruskal Wallis

‐ Chi-square (2)– rating distribution of the questionnaire ‐ P-value – significant difference in the mean ranks of critical factors

5

‐ Determine the statistically significant differences between the means of five stakeholder groups ‐ Ensure the robustness of the results from nonparametric Kruskal Wallis test

Parametric One-Way ANOVA

‐ P-value – significant difference in the means of critical factors

6

‐ Compare the differences in relative significance of factors between two independent groups

Non-parametric Mann Whitney test

‐ Probability value on critical decision-making factors ‐ P-value – significant difference in the mean ranks of critical factors between five groups of stakeholders.

7

‐ Compare the significant differences of factors between mean scores of two independent groups ‐ Ensure the robustness of the results from nonparametric Mann Whitney test

Parametric 2-sample t test

‐ P-value – significant difference in the mean ranks of critical factors

8

‐ Correct for type I errors in multiple comparison

Benjamini-Hochberg procedure

‐ P-corrected ‐ Correcting the significant P value that corresponding critical factors figured out from Kruskal Wallis and Mann Whitney tests

In addition, the robustness of survey quantitative analysis was confirmed by

conducting correlational tests in both nonparametric and parametric statistical


analysis. In this research, there were two equivalent pairs of hypothesis tests, which

were nonparametric Kruskal Wallis and parametric One-Way ANOVA, and

nonparametric Mann Whitney and parametric 2-sample t test. Further, the parametric

approach was used to examine whether there were any differences in stakeholder

groups’ perspectives. Moreover, the validity of the nonparametric statistical analysis

was increased by this approach.

As the distributions of survey data were identified non-normal by normality test, the

parametric approach required a data transformation. The data transformation was done

by logarithmic transformation in SPSS to make data conform to normality, which was

more appropriate for parametric testing (Changyong et al., 2014).

When testing for a statistically significant difference between two or five groups of

stakeholders, each critical factor is tested separately by Kruskal Wallis and Mann

Whitney tests and a p-value is computed for each critical factor. If the test results

provide the probability rate lower than 5% (p-value <0.05), the different perspectives

among two or five groups is statistically significant. These significant differences were

detected further by One-Way ANOVA and 2-sample test testing by p-values <0.05.

Furthermore, it is also important to correct the p-value of each critical factor to control

the type errors I in multiple tests. In this research, the False Discovery Rate (FDR) was

controlled with the Benjamini-Hochberg procedure (Benjamini & Hochberg, 1995).

Multiple testing corrections adjust the individual p-value generating a Benjamini-

Hochberg FDR – p-corrected value, which is used instead of convention rate of 5%.

The p-corrected is calculated by the following equation:

p-corrected =

where i is the rank of ascending input p-values; m is the total number of tests; and Q

is critical value for a false discovery rate. The largest p-value <p-corrected is

significant and all of the p-values smaller than it are also deemed significant. In this

research, the Benjamini-Hochberg critical value for a false discovery rate Q is chosen

to be 0.25, which is similar to the research of García‐Arenzana et al. (2014).

Regarding the results of the Kruskal Wallis test, if the difference was significant, the

Benjamini-Hochberg procedure was then applied to correct type I errors in multiple

comparisons. The Benjamini-Hochberg procedure was also used to correct p values

generated in the Mann Whitney test.


Based on the statistical nonparametric analysis, the results were then validated by

parametric testing and Benjamini-Hochberg procedure to identify 24 critical decision-

making factors. The finalised list of critical factors was verified by 22 practitioners in

Vietnam through interview study to ensure the influences and discussion of the

potential improvements of DW management.

3.6.3 Interview

According to Rogers and Bouey (1996), interviewing as a data collection technique in

post-positive research is a fairly common practice and involves the preparation of a

guide that lists a predetermined set of questions for the purpose of eliciting information

from participants. The semi-structured format provides a great amount of flexibility

and allows new questions and insights to be included during the course of the

interviews. The interviewees were identified and selected through purposive sampling

based on their familiarity with the subject matter. The interview questions were both

specific and open-ended and focused on major issues pertaining to the phenomenon

under investigation (Creswell & Plano Clark, 2011). Specific interview guides were

developed in order to ensure the common understanding among different stakeholders

working in different organisations, including government agencies, academic

institutes, and contractors.

The main purpose of the interview was to gather more in-depth information of each

critical factor explored from the survey for analysing data and validating the

framework. The interviewees were selected from those who engaged in the survey,

who expressed interest in participating in the interview (question 18 in the

questionnaire sample, Appendix A). A total of 29 survey respondents who stated their

willingness to involve in the interview were approached.

The sample criteria of selecting interviewees comprised the personal background,

experience, current positions, availability for the interview, and representation of

targeted organisations and cities in Vietnam. The background of the interviewees was

relevant to one of the disciplines in project management such as waste management,

urban planning, civil engineering, and sustainable development. In addition, 10-years

experience was required to ensure the interviewees’ in-depth understanding about the

research topic. The current positions of the interviewees were also considered in order

to identify the important roles in DW management decision-making in urban

redevelopment projects. Each participant was approached to check if they met the


criteria and be available in the interview period (from April to June 2017). Finally, the

22 selected interviewees represented for organizations and cities sampled in the survey

as well as five groups of key stakeholders, including academics, planners, consultants,

engineers, and policy makers.

Therefore, of the 29 participants, 22 interviewees were selected to participate in the

interview. The final 22 interviewees comprised four academics, three planners, three

consultants, six engineers, and six policy makers. The samples represented of all five

stakeholder groups are defined in section 3.6.2. All of the 22 interviewees had more

than 10 years of experience and held key positions in the projects.

Fourteen interviews were conducted face-to-face at the offices of interviewees, or at

coffee shops. Eight interviews were conducted by telephone. The interviews were

carried out in Vietnamese and each lasted an average of 45 minutes. An audio recorder

was used to record most of the interviews, and notes were also taken as a back-up.

Some interviewees objected to being recorded, out of fear of reprisals by superiors.

This request was adhered to by the researcher and detailed handwritten notes were

taken instead. Under the conditions of confidentiality, the names, positions and duty

stations of interviewees are not disclosed in this research.

Interviewees were asked to share their opinion regarding the importance of critical

factors in decision-making process of urban redevelopment DW management.

Interviewees were also requested to discuss the action plans for improving urban

redevelopment DW management in Vietnam. The semi-structured format provided a

great amount of flexibility and allowed new questions and insights to be included

during the course of the interviews.

The qualitative thematic analysis was then adopted to analyse the data collected from

the interviews to identify the influences of 24 critical factors on DW management in

the context of Vietnam. The results of the interview stage also provided the action

plans in accordance with critical factors suggested by the interviewees to improve DW

management in urban redevelopment projects in Vietnam. Due to the small sample

size of the interview, there was no benefit to be obtained from applying electronic

cognitive or pattern mapping software. Therefore, a manual method to transcription

analysis was adopted to pinpoint the key themes in terms of influencing and improving

DW management in Vietnamese urban redevelopment projects.


In the interview study, six critical decision-making factors were identified as crucial

information to develop a critical supporting database of DW management in GIS-

based model in the case study.

3.6.4 Case study

According to Adams, Khan, Raeside, and White (2007), the case study is the most

suitable method through which to identify best practice. There are three criteria to

achieve an effective case study, including using multiple sources of evidence;

establishing a database; and maintaining a chain of evidence (Yin, 2013). Accordingly,

the main purpose of the case study was to practically develop the supporting database

in the GIS-based model. The crucial data and practical concerns were identified from

the results of the survey and interview analysis involving the case study.

In this research, the case study was used as a practical example of how the supporting

database was developed in GIS-based model. This supporting database was considered

crucial information for improving decision-making process of urban redevelopment

DW management in Vietnam. Four mega urban redevelopment projects in Ba Dinh

district in Hanoi, Vietnam, were selected to develop the DW database. Both spatial

and attribute data were collected and analysed in GIS-based model at the district level.

Based on the case study method, this research introduced an approach of GIS

technology as a decision support tool that assists the decision makers in assessing and

qualifying the information about DW management.

In academia and practice, GIS-based model has been adopted in the fields of municipal

solid waste management and C&D waste management. According to Chalkias and

Lasaridi (2011), GIS is one of the most sophisticated modern technologies providing

tools to capture, store, manipulate, analyse and present spatial data. The data is

presented in thematic layers in the form of digital maps. These data are integrated with

the advanced related technologies to assist in the recording of spatial data and the direct

use of data for analysis and cartographic display. There were several approaches of

GIS-based model in municipal solid waste management such as siting waste

management, disposal facilities, optimising waste collection and transport (Chalkias

& Lasaridi, 2011). Karadimas and Loumos (2008) added that GIS has been

successfully adopted for sitting of recycling storage centres, estimating waste

generation, and predicting waste generation.


In the field of C&D waste management, GIS technologies were adopted in C&D waste

management such as reducing construction waste, quantifying DW flow, analysing

spatial construction materials (Li, Chen, Yong, & Kong, 2005; Tanikawa &

Hashimoto, 2009; Wu et al., 2016). The study by Li, et al. (2005) was to integrate GIS

with a Global Position System to minimise the amount of on-site waste by combining

construction materials and an equipment system based on the Wide Area Network.

While Tanikawa and Hashimoto (2009) and Wu, et al. (2016) use a GIS-based model

to estimate overall DW generation volume for aging stock at the regional level such as

Shenzhen city, China, Manchester, UK, and Wakayama city, Japan. In addition,

Tanikawa and Hashimoto (2009) present spatial distribution of construction materials

over time and clarified material accumulation with vertical location. Furthermore, Al-

Saggaf and Jrade (2015) integrate GIS with Buiding Information Modeling (BIM) in

DW estimation, classification, and transport at the project level. Similarly, Kleemann,

Lederer, Rechberger, and Fellner (2017) adopted GIS technology in analysing the

spatial distribution of construction materials used for the Vienna’s building stocks

regarding material components of various construction types, construction periods,

and the statistics of building structures.

By applying GIS technology, it is feasible to develop a database so that the spatial and

attribute analysis can support decision-making process. In the context of a case study

in Hanoi, Vietnam, this research used GIS-based model as the decision support system

for developing the critical DW database. The process of developing the GIS-based

model is presented in Figure 3-4.

The model of GIS allows the expression of the database in different forms, such as

maps, tables, and figures. The results of the case study were the DW volume estimation

for single building and single project; the volume of DW compositions such as bricks,

mortar and concrete, and metal; the number of trucks for inert DW (bricks, mortar, and

concrete) delivery; and options of choosing landfill sites.

The DW management database in GIS-based model in the case study was integrated

with 24 critical decision-making factors analysed and verified in the survey and

interview study in order to finalise the decision-making framework. This framework

provides critical factors and useful supporting database that decision makers can

consider in improving DW management in urban redevelopment projects at district

level.


3.7 ETHICAL CONSIDERATIONS

This study has been approved by the Human Research Ethics Committee (HREC) at

Queensland University of Technology. The QUT’s HREC confirms that the research

satisfies all necessary conditions set by the National Statement on Ethical Conduct in

Human Research regarding the participants’ rights and welfare in the survey study and

the interview study. The reference approval number of this research is 1600000588.

The respondents were voluntarily involved in the research and their decisions to

participate or not does not influence on their relationship with Queensland University

of Technology.

The research findings which were clarified to the participants do not directly impact

on their benefits. Instead, the research enriches their existing knowledge related to the

improvement of DW management in urban redevelopment projects, in which the

exploration and evaluation of the influences critical factors in the decision-making

Figure 3-4: Process of GIS-based model for the development of supporting database

Data collection

Spatial data

. Map/Satellite image of land-use . Map of transport . Locations of building and projects . Locations of C&D waste landfill site

Attribute data

. Structure information of buildings . Building components . C&D waste landfill locations and capacity

Estimation of DW volume (ton)

. Volume of DW composition

. DW volume of single building

. DW volume of single project

Choosing of landfill sites

. Distances to landfill sites

. Landfill capacity

Estimation of pick-up trucks

. The number of trucks for non- inert DW Integration of

spatial and attribute data


process are the main focus. The research findings will raise awareness about the

significance of sustainable urban redevelopment and the DW management.

In order for the participants to understand the research topic, the researcher introduced

the research purpose in the participant information sheet and provided consent forms

before asking them to fill out the questionnaires. Accordingly, the respondents can be

clear and confident in their participation. Since the consent form explains the

significance of the respondents’ participants, their decision to participate was agreed

by signing the consent form and sending it back to the researcher.

3.8 SUMMARY

This chapter elaborates the methodological steps that were undertaken to develop the

decision-making framework for improving DW management in urban redevelopment

projects. The quantitative and qualitative analyses were adopted in different research

stages to deal with the research questions, address the research objectives, and achieve

the research aim.

The research development process includes three main stages: establishing the

conceptual framework, developing the framework, and developing the supporting

database. Four main research methods were employed through the research process to

conduct research background investigation, data collection, and data analysis. These

were literature review, questionnaire survey, interviews, and case study, wherein two

data collection and analysis tools were used, namely SPSS and GIS. The data

collection and research findings are described in the next three chapters.

85

Chapter 4: Survey Study

4.1 INTRODUCTION

This chapter presents the data collected from the respondents who participated in

completing the questionnaire (see Appendix A). The findings from the analysis reveal

the critical decision-making factors for urban redevelopment DW management and the

conceptual framework of this research.

According to the research process, the survey study is an important stage in the data

collection phase. The survey was carried out after the conceptual decision-making

framework was established in the literature review. The questionnaire design, survey

instruments, the survey response rate, and validity are first described. The following

sections present the quantitative results to explore the stakeholders’ perspectives on

decision-making factors of urban redevelopment DW management and the critical

decision-making factors. Finally, the findings from the questionnaire survey are discussed

before the development of the conceptual decision-making framework of urban

redevelopment DW management.

4.2 QUESTIONNAIRE DESIGN

The questionnaire survey was employed to investigate the stakeholders’ perspectives

regarding decision-making on urban redevelopment DW management. The survey was

designed based on the theoretical decision-making factors identified in the background

literature with a synthesis and compilation process, resulting in the consolidation of 53

decision-making factors to be investigated. The questionnaire in this research is

developed on the Key Survey software. A pilot study was carried out to examine the

feasibility of the approach prior to performance of a full-scale research project that was

able to gather the expected data. Fellows and Liu (2015) indicate that the pilot survey is

also conducted to ensure the clarity, comprehensiveness and acceptability of the

questionnaire. A group of five respondents, including two university professionals, one

construction engineer, and one consultant, was asked to validate the questionnaire.

Respondents were asked for the extent of the clarity, language, design, and the

effectiveness, to minimise the problems of misinterpretation or misreading of the

86 Chapter 4: Survey Study

questions. No major changes were required, and the questionnaire contains five parts,

utilising a combination of multiple-choice questions, rating scale, and open-ended

questions. The samples of the questionnaire survey, including in English and Vietnamese,

are attached in Appendix A1 and A2.

The structure of the survey itself will be described as follows. The questionnaire consists

of five steps: (1) Respondent information, (2) General information, (3) Factor affecting

the decision-making process of DW management in urban redevelopment projects, (4)

Further information and (5) Optional question, as shown in table 4.1. In the first part of

the questionnaire, the respondents’ profiles are considered important to gather. This is

because the data reliability is based on the data source and the background of the person

who participates in the questionnaire survey (Ahuja, Yang, & Shankar, 2010). The

second part captured the general information regarding the DW management in urban

redevelopment projects. Part 3 is the main section of the survey, which required the

respondents to rate the importance of the potential decision-making factors using a 5-

point Linkert-scale from 1 representing ‘Not at all important’ to 5 representing

‘Extremely important’. Part 4 employed multiple choice questions and open text sections

for respondents to offer further information and additional recommendations. Finally, in

part 5, the respondents were asked to participate in the interview stage of this research.

Five groups of respondents' roles were investigated in the survey samples, namely,

academics, planners, consultants, engineers and policy makers who were directly

involved in the urban redevelopment DW management in Vietnam. The respondents were

asked to assess the significance of the decision-making factors based on their work

experience.

The respondents in the survey were selected from 54 organisations in three main cities in

Vietnam (Hanoi, Hai Phong, and Ho Chi Minh City) and were from different

organisations, such as the Ministry of Construction; Ministry of Natural Resources and

Environment; Ministry of Science and Technology; academic institutes (University of

Construction, Hanoi University of Science, Hanoi University of Natural Resources and

Environment); Construction companies, and Environmental Service companies in both

government and private sectors. These organisations are the professional institutions

involved in urban redevelopment DW management in Vietnam.

87

Table 4-1: Structure of the questionnaire

No. Category Purpose

1 Respondents’ information

To collect the respondents’ basic information for the purpose of categorisation, such as current position, type of organisation, professional experience, the role in the project.

2

General information relevant to urban redevelopment DW management.

To collect the information regarding the current implementation of DW management in urban redevelopment projects, such as the project location, the scale of the project, the network of stakeholders, the criteria of implementation of urban redevelopment projects.

3

Factors affecting the decision-making process of DW management in urban redevelopment projects

To collect the professional opinions of the determinant decision-making factors in urban redevelopment DW management. There were 5 categories of decision-making factors:

‐ Technical factors (16 factors): e.g., equipment of demolition projects, onsite sorting of demolition waste, planning the area for landfill, life cycle assessment.

‐ Environmental factors (11 factors): e.g., the willingness of DW management by stakeholders, understanding the uniqueness of demolition waste, 3R promotion, identifying the rate of recovery.

‐ Economic factors (8 factors): e.g., estimating the cost of demolition, cost-effective demolition plans, developing of recycling market.

‐ Social factors (9 factors): e.g., the role of community in decision-making process, effective feedbacks from community, job creation due to DW management.

‐ Institutional factors (9 factors): e.g., the role of key stakeholders in monitoring and feedbacks, providing guidelines of DW management plan, regular information update.

4 Further information relevant to urban redevelopment DW management

Further comments and opinions regarding the research topic are collected.

5 Optional question The respondents were invited to provide their contact details if they were able to participate in the interview round of this research.

4.3 SURVEY INSTRUMENT

The survey was carried out using two approaches of survey distribution to collect answers

from the survey participants, namely the online questionnaire and the face-to-face


questionnaire survey. For the online questionnaire, the survey was carried out through an

online survey platform, called ‘Key Survey’, which can be accessed at

https://survey.qut.edu.au/site/.

There has been a growing trend of using the Internet and email for conducting the

questionnaire survey in the last two decades (Neuman, 2000). The advantages of an online

survey are reducing cost and time, gathering information from a large audience and

allowing respondents to maintain their anonymity (Van Selm & Jankowski, 2006). In

addition, the instant reports from the online survey can support the researcher to monitor

the data information, such as the number of participants and the amount of time spent

answering the questionnaire. This online tool can be flexibly designed and is at the

researcher’s disposal in achieving the research objectives.

Another method of survey distribution in this research was the face-to-face questionnaire

survey. This method was expected to gain higher response rates in comparison with other

methods. Face-to-face questionnaire survey was employed due to lack of response to the

questionnaire by potential respondents in the sample via the online survey method. The

participants were approached via phone or email before the researcher met them and

asked them to fill in the questionnaire.

4.4 SURVEY RESPONSE RATE AND VALIDITY

The survey was conducted from September 2016 to January 2017. In total, 500 survey

invitations were sent to the participants with the cover letter (Appendix A3), the consent

form and the questionnaire link or hard copy. The purpose of the research and assurances

of confidentiality are carefully stated in the cover letter. A total of 216 valid responses

were received in the questionnaire survey. The valid responses to the survey questionnaire

were ensured as to whether the questions were fully responded, whether there were any

irrational answers such as rating the same score for all questions, and whether the

respondent’s profile showed the limitations of experience in the field of urban

redevelopment DW management.

As mentioned above, this research employed two methods of survey distribution for the

questionnaire survey, namely the online questionnaire and the face-to-face questionnaire

survey. The combination of different data collection approaches can help the researcher

gain higher response rate of the survey. The responses received by each of the methods

are presented in the following.

89

Online questionnaires: The participants in the online survey were contacted via email to

be informed about the survey. The participants completed and returned the questionnaire

in about four weeks and the polite reminder postcard was sent to remind the participants

who did not complete the questionnaire in the survey period. After the allocated period

for responding to the online survey, out of 183 respondents, 166 responses were fully

completed and were considered valid for data analysis. The overall response rate for the

online questionnaire method was 33.2%. This low response rate may have been due to

the limited time available for working on the computer, especially for the participants

working on construction sites.

Face-to-face questionnaire survey: Due to the low response rate received from the online

survey, the researcher decided to use the method of face-to-face questionnaire survey to

conduct the questionnaire survey, helping to collect information from another 50

respondents. The response rate was 100% because the appointments with the participants

were made in person. The survey strictly followed the online questionnaire and the

researcher had explained any ambiguous survey questions or information during the

meeting. Therefore, all the responses were considered valid for data analysis.

Consequently, the response rate of both survey methods was 43.2%, corresponding with

the total number of 216 out of the total of the targeted number of 500 respondents. This

figure is well above the acceptable response rate, exceeding the normal rate of

approximately 30% in the construction industry (Akintoye, 2000; Love & Smith, 2003).

4.5 QUESTIONNAIRE RESULTS AND ANALYSES

4.5.1 Respondents’ profiles

As discussed above, the respondents’ profiles regarding their background, qualifications,

and experience are asked in Part A of the questionnaire. The 216 valid respondents across

the classification of their professional positions were categorised in five groups Table

4.2). The highest number of respondents was from the engineer group, including

construction engineers and environmental engineers, accounting for 26% of the total

number of respondents. This was followed by the academic group (24%), policy maker

group (20%) and planner group (17%). The consultant group was less interested in the

survey, representing only 13% of the responses.


Table 4-2: Respondents’ information

The distribution of the respondents by organisation type is illustrated in Table 4.2. Out of

the 216 respondents, 33% were from research institutions, 22% were from the

government agency and 21% were from the local authority. The respondents from

contractors of construction and waste management were 16% and 8%, respectively. The

low rate of respondents from waste management contractors is attributed to the poor

environmental services for C&D waste in Vietnam.

Regarding respondents’ experience, all of the respondents surveyed have experience in

DW management in urban redevelopment projects. The respondents’ length of working

experience was reliable data across five groups (Table 4.2). Around 55% of the

respondents have had at least 10 years of experience in the field that the research topic

No Distribution of respondents Frequency Valid percent

1 Respondents’ profession

Engineer 57 26

Academic 51 24

Policymaker 42 20

Planner 37 17

Consultant 29 13

2 Type of organisations

Research institution 72 33

Government agency 47 22

Local authority 45 21

Construction contractor 34 16

Waste management contractor 18 8

3 Respondents’ experience

Under 5 years 15 7

5-10 years 82 38

10-15 years 65 30

15-20 years 41 19

Over 20 years 13 6

4 Frequency of involvement in demolition waste management

Rarely 21 10

Sometimes 82 38

Often 71 33

Always 42 19

91

deals with, whereas 6% of the respondents were stated to have had experience for over

20 years. This high level of respondent seniority enables the high credibility and high

quality of data collection. However, there were about 45% of respondents with under 10

years’ experience in urban redevelopment DW management.

There were 52% of the respondents who were often and always involved in urban

redevelopment DW management (Table 4.2). Around 38% of the respondents sometimes

participated in the field of the research topic and 10% were rarely engaged in DW

management in urban redevelopment projects. This may due to the fact the urban

redevelopment activities are quite new issues in Vietnam over the last decade.

The majority of the respondents undertaking urban redevelopment projects were from

Hanoi, accounting for 134 out of 216 respondents (Figure 4-1). The number of

respondents from Hai Phong and Ho Chi Minh cities was lower than in Hanoi, with 42

and 40 respondents, respectively. This figure represented the current status of urban

redevelopment in those cities in Vietnam, whereas Hanoi is the leading city in urban

redevelopment issues.

Figure 4-1: Distribution of the respondents by the places in which they implemented the urban redevelopment projects

0

20

40

60

80

100

120

140

160

Hai Phong Hanoi Ho Chi Minh city

Number ofparticipants


4.5.2 Reliability of the questionnaire

The SPSS Statistics 23.0 program was used in evaluation in order to understand whether

measurement instruments were reliable and valid. Table 3-3 in Chapter 3 shows the

results and meanings of the reliability tests for different measurement scales.

Before the study proceeded with the analysis, the internal consistency of the measurement

scales for 53 decision-making factors was evaluated upon the calculation of Cronbach’s

Alpha, which normally ranges between 0 and 1. Pallant (2010) suggests that when the

value of Cronbach’s Alpha is above 0.7, the data is deemed to be reliable while the alpha

value of greater than 0.8 is often preferred. In addition, Darren and Mallery (1999) set

thresholds for evaluating reliability upon the value of Cronbach's alpha that the reliability

of measurement scales is deemed to be excellent, good, acceptable, questionable, poor or

unacceptable if the Cronbach’s Alpha is greater than 0.9, between 0.8 and 0.8; between

0.7 and 0.8; between 0.6 and 0.7; between 0.5 and 0.6 and less than 0.5 accordingly. Since

the Cronbach's alpha value for identified decision-making factors in urban redevelopment

DW management was 0.847, the reliability of the measurement scales and data was

evaluated as good.

4.5.3 Respondents’ perspectives

This section focuses on the rating of decision-making factors influencing the DW

management in urban redevelopment projects. The average mean score and standard

deviation were calculated for each potential decision-making factor to figure out its level

of importance and spread dispersion. These figures were different among the five

stakeholder groups. The mean values of the 53 potential decision-making factors range

from 2.45 to 4.44, which illustrates a discrepancy in significance among various decision-

making factors. The modest values of standard deviation (0.475 to 0.732) indicate an

insignificant diversity in the respondents’ ratings.

The mean and standard deviation of each decision-making factor are calculated from the

total sample to identify the level of importance. The standard deviation illustrates the

extent of variation from which the mean value is calculated. In this research, all of the

standard deviation values are smaller than 1.0 that affirms the data accuracy. If two or

more factors have the same mean value, the one with the lower standard deviation is

ranked as more important. The respondents’ perspectives are discussed in detail below.

93

4.5.3.1 Perspective of Academics

The findings as set out in Appendix B2 indicate that the impact level of decision-making

factors for urban redevelopment DW management according to 52 academics differs to

that of factors identified by other stakeholders. Among five categories of decision-making

factors, academics ranked institutional factors as the most important in decision-making

urban redevelopment DW management (mean value = 4.07) (Table 4-3). This is followed

by technical factors and environmental factors, with mean value of 3.951 and 3.970,

respectively. Social factors, conversely, were the least important (mean value = 3.368).

Table 4-3: Academics’ ratings of decision-making factors of demolition waste management

No. Decision-making

factors Number

of factors

Rank Mean

Std. Deviation

Minimum Maximum Minimum Maximum

1 Technical factors 16 3 5 3.951 .497 .706

2 Environmental factors

11 2 5 3.970 .525 .700

3 Economic factors 8 2 5 3.914 .563 .705

4 Social factors 9 1 5 3.368 .518 .759

5 Institutional factors 9 3 5 4.076 .473 .687

In general, out of 53 factors, 23 factors have been ranked by academics as very important,

with the mean value of more than 4.00. Three highest ranked decision-making factors are

‘guidelines of DW management’ (mean = 4.412), ‘on-site sorting’ (mean = 4.392),

‘determining the procedure’ (mean = 4.373). With regards to technical value, the results

express that the academics were more concerned about ‘on-site sorting of DW’ (mean

value = 4.392), ranking it as the most important factor in this category. This is the priority

factor in DW management (Poon, et al., 2001). Meanwhile in the category of

environmental factors, ‘promotion of 3R’ was ranked as the most important factor of

decision-making in urban redevelopment DW management (mean = 4.314). ‘Cost-

effectiveness of demolition plan’ was considered as the most important factor in the

economic category (mean = 4.333). ‘Preservation’ was identified as the most important

social-cultural factor, indicating the goal of sustainability in urban redevelopment

projects (mean = 4.255). In term of institutional factors, ‘guidelines of DW management’


was in the first of the list for it topped the list in terms of the importance in improving

decision-making of urban redevelopment DW management (mean = 4.412).

4.5.3.2 Perspective of Planners

The findings as set out in Appendix B3 indicate that the impact level of decision-making

factors for urban redevelopment DW management, according to 37 planners, differs from

that of factors identified by other stakeholders. Among five categories of decision-making

factors, planners ranked institutional factors as the most important in decision-making

urban redevelopment DW management (mean value = 4.180) (Table 4-4). This is

followed by technical factors and environmental factors, with mean value of 3.867 and

3.26 respectively. In the meantime, social factors were the least important (mean value =

3.330).

Table 4-4: Planners’ ratings of decision-making factors of demolition waste management

No. Decision-making

factors Number of

factors

Rank Mean

Std. Deviation




11 2 5 3.826 .479 .731


4 Social factors 9 1 5 3.330 .442 .758


In general, out of 53 factors, 24 factors have been ranked by planners as very important

with the mean value of more than 4.00. The three highest ranked decision-making factors

are ‘guidelines of DW management’ (mean = 4.568), ‘information update’ (mean =

4.459), ‘on-site sorting’ (mean = 4.405). Similarly, to the results of academics’

perspective analysis, planners were more attentive to on-site sorting of DW (mean value

= 4.405), ranking it as the most important factor in this category. In the category of

environmental factors, ‘promotion of 3R’ was ranked as the most important factor of

decision-making in urban redevelopment DW management (mean = 4.270). ‘Cost-

effectiveness of demolition plan’ was considered as the most important factor in the

economic category (mean = 4.351). ‘Preservation’ was identified as the most social

95

factor, indicating the goal of sustainability in urban redevelopment projects (mean =

4.162). In terms of institutional factors, ‘guidelines of DW management’ was the first of

the list in terms of its importance in improving decision-making of urban redevelopment

DW management (mean = 4.568).

4.5.3.3 Perspective of Consultants

As depicted in Appendix B4, 29 consultants participating in the survey rated the impact

level of decision-making factors for urban redevelopment DW management differently

from that of factors pinpointed by other stakeholders. Among the five categories of

decision-making factors, institutional factors were given the greatest significance in

decision-making urban redevelopment DW management, which reflected a similar

pattern to the perspectives of academics and planners (mean value = 4.050) (Table 4-5).

What followed were technical factors and environmental factors, with mean value of

3.9659 and 3.881, respectively. In contrast, social-cultural factors were quoted as the least

important of all (mean value = 3.341).

Table 4-5: Consultants’ ratings of decision-making factors of demolition waste management

No. Decision-making

factors Number of

factors

Rank Mean

Std. Deviation




11 2 5 3.881 .516 .677


4 Social factors 9 2 5 3.341 .484 .689


In general, out of 53 factors, 18 factors were ranked by consultant group as very important

with a mean value is greater than 4.00. The following five decision-making factors were

ranked as the most important by consultants: ‘determining the procedure’ (mean =

4.5217), ‘on-site sorting’ (mean = 4.448), ‘willingness of stakeholders’ (mean = 4.379),

‘guidelines of DW management’ (mean = 4.379), ‘information update’ (mean = 4.379).

With respect to technical value, the results reveal that the consultants assigned the most


important factor to ‘determining the procedure’ in this category (mean = 4.517), while in

the category of environmental factors, ‘the willingness of stakeholders’ was rated as the

most significant factor of decision-making in improving of urban redevelopment DW

management (mean = 4.379). ‘Cost-effectiveness of demolition plan’ was regarded as the

most important factor in the economic category (mean = 4.138). ‘Preservation’ was

identified as the most important social factor (mean = 4.345). With respect to institutional

performance, ‘guidelines of DW management’ was at the top of the list for its importance

in improving decision-making of urban redevelopment DW management (mean = 4.379).

On the other hand, ‘accomplishing government’s policy and strategy on DW

management’ was rated as the least important factor (mean = 3.759).

4.5.3.4 Perspective of Engineers

As indicated in the results summarised in Appendix B5, 57 engineers were asked to rate

the impact level of decision-making factors for urban redevelopment DW management.

Among the five categories of decision-making factors, engineers ranked institutional

factors as the most important in decision-making urban redevelopment DW management,

which is pretty similar to other groups’ perspective on this category (mean value = 4.175)

(Table 4-6). The technical factors’ value was ranked second with mean value of 4.010.

This is closely followed by economic performance with mean value of 3.974.

In general, 23 out of 53 factors have been ranked by engineers as very important

determinants with the mean value of more than 4.00. The three following decision-

making factors were ranked by engineers as the most important: ‘on-site sorting’ (mean

= 4.491), ‘information update’ (mean = 4.474), ‘determining the procedure’ (mean =

4.421).

With regards to technical factors, the results investigate that the engineers ranked ‘on-site

sorting’ as the most important factor in this category (mean = 4.491). This is followed by

two factors of ‘determining the procedure’ and ‘GIS-based model for DW management’,

while in the category of environmental factors, ‘promotion of 3R’ was rated as the most

important factor of decision-making in improving of urban redevelopment DW

management. ‘Cost estimation of waste transport’ was considered as the most important

factors in the economic category (mean = 4.386). ‘Preservation’ was also identified as the

most social important factor (mean = 4.351).

97

Table 4-6: Engineers’ rating of decision-making factors of demolition waste management

No. Decision-making

factors Number

of factors

Rank Mean

Std. Deviation




11 2 5 3.821 .495 .682


4 Social factors 9 1 5 3.480 .481 .774


The factors of ‘effective feedback by community’ and ‘community monitoring’ were

ranked as not overly important decision-making factors in urban redevelopment DW

management, with the value of 2.667 each. Concerning institutional performance,

‘regular information update’ was rated as the most important factor in improving

decision-making of urban redevelopment DW management.

4.5.3.5 Perspective of Policy makers

As indicated in the results summarised in Appendix B6, 43 policy makers were invited to

take part in the survey to rate the impact level of decision-making factors for urban

redevelopment DW management. Among the five categories of decision-making factors,

institutional factors occupied the most important part in decision-making urban

redevelopment DW management, which is similar to other groups (mean value = 4.116)

(Table 4-7). The environmental factor value ranked second, with a mean value of 3.91,

while the policy maker group rated the technical performance less important than

economic performance, with mean values of 3.839 and 3.866, respectively.

In general, out of 53 factors, 23 factors have been ranked by policy makers as very

important, with mean value of more than 4.00. The three following decision-making

factors were ranked by engineers as the most important: ‘guidelines of DW management’

(mean = 4.524), ‘preservation’ (mean = 4.429), ‘promotion of 3R’ (mean = 4.381).


Table 4-7: Policy Makers’ rating of decision-making factors of demolition waste management

No. Decision-making

factors Number

of factors

Rank Mean

Std. Deviation




11 1 5 3.909 .412 .777


4 Social factors 9 1 5 3.381 .495 .763


Regarding technical value, the results show that the policy makers rated ‘determining the

procedure’ as the most important factor in this category (mean = 4.333). This is followed

by two factors of ‘on-site sorting’ and ‘landfill planning’, with the mean values of 4.310

and 4.143, respectively. Similarly, to the engineers’ perspectives, in the category of

environmental factors, ‘promotion of 3R’ was rated as the most important factor of

decision-making in improving urban redevelopment DW management. The two factors

of ‘disposal control fee’ and ‘balancing of greenhouse gas’ were rated as the not too

important factors influencing decision-making of urban redevelopment DW management,

with the mean values of 3.619 and 3.048, respectively. ‘Cost-effectiveness of demolition

plan’ was considered as the most important factor in the economic category (mean =

4.310) and ‘cost for waste disposal’ was the least important (mean = 3.190).

‘Preservation’ was also identified as the most social important factor (mean = 4.429). The

factor of ‘effective feedback by community’ was ranked as a not too important decision-

making factor in urban redevelopment DW management, with the value of 2.595. As for

institutional performance, ‘guidelines of DW management’ was ranked as the most

important factor in improving decision-making of urban redevelopment DW

management, whereas ‘stakeholder feedback role’ was considered as the least important

factor (mean = 3.738).

4.5.4 Comparison of rankings among five groups of respondents

The key stakeholders’ perspectives on decision-making factors influencing urban

redevelopment DW management varied, according to the function of their organisation,

99

their experience and their roles in DW management projects. A comparison of rankings

of decision-making factors among key stakeholders is illustrated in Table 4-8.

In regard to technical value, engineers (G4) were more concerning than four other groups:

academics (G1, planners (G2), consultants (G3), and policy makers (G5), with mean

value was greater than 4.0. Two factors of ‘on-site sorting’ and ‘determining the

procedures’ were ranked in the top ten of all decision-making factors by all groups, with

the mean values of 4.412 and 4.384, respectively. There were differences in rating the

most important technical factor: ‘on-site sorting’ that ranked in eighth place by policy

makers (G5) and ranked in top three important factor by four other groups: academics

(G1, planners (G2), consultants (G3), and engineers (G4). Meanwhile, all five groups

rated ‘estimation of DW’, ‘landfill planning’, ‘choosing demolition method’ and ‘training

of demolition techniques’ as the top 26 decision-making factors for urban redevelopment

DW management, with the mean values ranging from 4.032 to 4.213. In addition, all five

respondent groups had little awareness of ‘life cycle assessment’ in improving urban

redevelopment DW management, with mean value of 3.347.

The environmental performance category received more concerning by academics (G1)

and policy makers (G5) than three other groups: planners (G2), consultants (G3), and

engineers (G4), with mean value was greater than 3.9. It is understood that environmental

issues are placed as important criteria in developing C&D waste policy in Vietnam. The

factor of ‘promotion of 3R’ was ranked in the top ten of the given decision-making factors

by the groups: academics (G1), planners (G2), consultants (G3) and policy makers (G5),

while the engineers (G4) agreed that this factor occupied the fifteenth place (mean =

4.282). On the other hand, ‘balancing of greenhouse gas’ was ranked in the five least

important decision-making factors by all groups (mean = 2.986).

According to the mean score, ‘cost-effectiveness of demolition plan’ was rated to be the

most important economic factor for improving urban redevelopment DW management in

Vietnam, with mean value of 4.306. Followed by ‘cost estimation of waste transport’,

with the mean value of 4.176 and engineers (G4) showed higher concern on this factor

than four other stakeholder groups. Also, ‘estimation of demolition cost’ was rated as a


very important decision-making factor, which was in the top 25 of the list, except for the

rating of the consultant group (mean = 4.042). The factor of ‘developing of disposal cost’

was deemed to be the least important economic factor by all five stakeholder groups,

which ranked forty-eighth out of 53 factors (mean =3.273).

In the social category, ‘preservation’ and ‘disturbance’ were rated by all groups as very

important social factors, with mean values of 4.310 and 4.111, respectively. However,

policy makers (G5) were more concerning on these two important factors than four other

groups: academics (G1), planners (G2), consultants (G3), and engineers (G4). On the

other hand, ‘community’s support’, ‘community’s role’, ‘community’s monitoring’ and

‘community’s feedback’ were ranked in the five least important social factors by all five

groups, with the mean ranging from 2.583 to 2.931. It is surprising to see that although

many social factors have been considered as significant factors in Vietnamese urban

redevelopment projects, the social factors were ranked relatively low in the survey.

With respect to institutional performance, the highest ranking was ‘guidelines of DW

management’ among three groups: academics (G1), planners (G2) and policy maker (G5)

(mean = 4.444). This ranking was slightly different with two other groups: consultants

(G3) and engineers (G4), which ranked fourth and sixth respectively. ‘Information

update’ was rated in the top five of the list, but received a relatively lower rating by the

academic group (mean = 4.398). The three factors of ‘stakeholders’ responsibility’,

‘stakeholder feedback role’ and ‘understanding DW management procedure’ were ranked

by all groups as very important decision-making factors, ranking in the top 17 of the list

(mean > 4.200). The rest of the four decision-making factors – ‘stakeholders’ involvement

in early stage’, ‘control meeting’, ‘accomplishing policy’ and ‘stakeholders’ feedback’ -

were ranked by all groups in the top 35 of the 53 decision-making factors.

Table 4-8: A comparison of ratings of decision-making factors for urban redevelopment DW management among key stakeholders

No. Decision-making factors Rank Mean Ranking according to professional groups

G1 G2 G3 G4 G5

I. Technical factors

101


G1 G2 G3 G4 G5

1 On-site sorting/separating of demolition waste

2 4.412 2 3 2 1 8

2 Determining the procedures of demolition waste management

4 4.384 3 9 1 3 6

3 Estimation of demolition waste 10 4.213 19 8 7 13 17

4 Planning the area for landfills 13 4.181 9 6 10 21 15

5 Choosing demolition method (reduction of demolition time, cost and waste)

15 4.130 21 17 19 11 18

6 Planning the area for sorting platform 21 4.051 13 22 15 23 26

7 Training the human resources in demolition techniques

23 4.032 25 23 23 14 24

8 Planning storage space for recyclable materials

24 4.028 24 15 11 35 22

9 The use of GIS-based modeling demolition waste management

27 3.889 20 45 32 10 42

10 Sufficient equipment for demolition project

33 3.815 36 28 26 30 36

11 The use of selective demolition method (on-site sorting, separate waste for reuse and recycling)

35 3.806 28 43 25 27 37

12 Identifying risks associate with building’s demolition

37 3.787 38 26 40 38 27

13 Managing time of the duration of demolition

39 3.741 41 31 41 37 32

14 The use of BIM-based in demolition waste management

41 3.713 40 39 21 34 45

15 Skilled personnel are available for conducting demolition project

46 3.380 43 48 44 46 47

16 Life cycle assessment 47 3.347 48 46 47 47 46

II. Environmental factors

1 Promotion of 3R in demolition waste management (reduction, reuse and recycling of demolition waste)

8 4.282 5 10 9 15 3

2 The willingness of demolition waste management by stakeholders

12 4.190 6 12 3 22 21

3 Understanding the uniqueness of demolition waste before demolition stage

16 4.125 16 11 8 31 19

4 Training the human resources in the integrated waste management

17 4.120 11 25 36 16 7



G1 G2 G3 G4 G5

5 Identifying rate of waste recovery 19 4.069 14 21 18 29 16

6 Environmental Impact Assessment 20 4.056 17 24 13 28 20

7 Understanding environmental issues of demolition waste generation

34 3.806 26 32 24 39 39

8 The use of recycled materials 38 3.778 32 36 38 40 28

9 Understanding of hazardous demolition waste

40 3.722 33 38 43 41 40

10 Disposal control (fee, landfill sites) 45 3.579 46 44 42 44 41

11 Balancing of greenhouse gases 49 2.986 49 51 49 51 49

III. Economic factors

1 Cost- effective demolition plans 7 4.306 4 5 16 8 9

2 Cost estimation of waste transport 14 4.176 18 18 27 5 12

3 Estimation of demolition cost 22 4.042 22 27 22 20 13

4 Cost estimation of waste treatment 26 3.912 37 34 35 18 23

5 Reducing cost of demolition waste transportation

30 3.856 29 33 29 26 33

6 Developing of recycling market 32 3.819 27 30 37 36 34

7 Saving the amount of energy use (fuels, electricity and others)

42 3.616 39 42 45 42 44

8 Developing an appropriate cost for waste disposal

48 3.273 47 47 48 48 48

IV. Social factors

1 Preservation of natural resources, cultural and heritage

6 4.310 8 14 6 7 2

2 Reduction of community disturbance during demolition stage (e.g. demolition noise, dust and other pollutions)

18 4.111 23 16 20 17 11

3 Reduction of risks, accidences for workers on demolition site

36 3.792 44 37 33 19 31

4 Job creation due to demolition waste management

43 3.616 42 40 46 43 38

5

Increasing public awareness of integrated demolition waste management/sustainable urban redevelopment

44 3.593 45 41 39 45 43

6 Community’s supportive actions before demolition stage

50 2.963 50 49 50 49 51

103


G1 G2 G3 G4 G5

7 The role of community in decision-making process

51 2.931 51 50 51 50 50

8 Community’s monitoring of environmental conditions during demolition stage

52 2.611 52 52 53 53 52

9 Effective feedback by community 53 2.583 53 53 52 52 53

V. Institutional factors

1 Providing guidelines of demolition waste management plan

1 4.444 1 1 4 6 1

2 Regular information update 3 4.398 7 2 5 2 5

3 Understanding of responsibilities by all stakeholders

5 4.329 10 4 14 4 4

4 The roles of key stakeholders in monitoring and feedback

9 4.259 12 7 12 9 10

5 Understanding of demolition waste management procedures

11 4.199 15 13 17 12 14

6 Involvement of key stakeholders in early stage

25 3.921 34 20 28 24 25

7 Demolition project control meeting 28 3.889 35 19 30 25 30

8 Accomplishing government’s policy and strategy on demolition waste management

29 3.856 31 29 34 32 29

9 Effective feedback by stakeholders 31 3.824 30 35 31 33 35

Note: G1- Academic; G2 – Planner; G3- Consultant; G4- Engineer; G5 – Policy maker

4.5.5 Critical decision-making factors for demolition waste management in Vietnamese urban redevelopment projects

In order to analyse the factors with relatively high mean values, which reflect a higher

level of impact on decision-making, a criterion is set in this research for the exploration

of those critical factors. In selecting critical decision-making factors, the factor with mean

values that is greater than 4.0 is classified as the critical decision-making factor in

influencing DW management. Based on 53 decision-making factors identified in the

literature review, 24 factors were ranked by respondents as ‘important’ and ‘very

important’, receiving a mean value of more than 4.0. Table 4-9 shows the level of

importance of the 24 critical decision-making factors for urban redevelopment DW

management, based on the questionnaire results.


The research findings reveal that the factor ‘Guidelines of DW management’ was ranked

at the first place among all important factors (mean value: 4.444). This finding echoes the

notion that ‘guidelines of DW management’ is the most important factor in DW

management (del Río Merino, et al., 2009). Furthermore, as expected, ‘on-site sorting of

DW’ was ranked as the second critical factor influencing DW management in urban

redevelopment projects (mean value: 4.412). Poon, et al. (2001) state that separation of

C&D waste onsite offers several benefits of waste treatment, such as less effort required

and better classification of inert and non-inert wastes in comparison with waste sorting

centrally conducted at a designated area on-site or off-site.

In the institutional factor group, the ‘Information update’ was ranked at the third place

(mean value: 4.398). This result is consistent with the finding by Kleemann, et al. (2014),

who recommended that providing the information of building materials prior to

demolition work is a prerequisite for the efficient recycling of DW. If urban

redevelopment projects’ participants access accurate and updated DW information when

making decisions, the DW management will be more efficient, particularly in reducing

and recycling waste.

It is also worth noting, that out of 16 technical factors in this research, 7 factors received

a high rating from the respondents, such as ‘determining the procedure of DW

management’, ‘landfill planning’, ‘Estimation of DW’, ‘choosing demolition methods’,

‘training of demolition techniques’, ‘sorting platform planning’ and ‘recycled materials

storage planning’. This finding echoes the results of several studies on C&D waste

management (Lu & Yuan, 2010; Lu, et al., 2011; Yuan, et al., 2011).

It should be noted that among 11 environmental decision-making factors, 6 factors were

ranked as important in DW management in urban redevelopment projects, which are

‘promotion of 3R in DW management’, ‘the willingness of stakeholders’, ‘the uniqueness

of DW’, ‘rate of recovery’, ‘environmental impact assessment’ and ‘training of DW

management’. This result reflects that respondents have perceived the environmental

impacts caused by DW.

Table 4-9: Factors rated by the respondents as important and very important (mean >4)

No. Decision-making Factors Mean Std.

Deviation Rank


4.444 .498 1

105


Deviation Rank

2 On-site sorting/separating of demolition waste 4.412 .521 2

3 Regular information update 4.398 .553 3


4.384 .524 4

5 Understanding of responsibilities by all stakeholders 4.329 .660 5


4.310 .511 6

7 Cost- effective demolition plans 4.306 .646 7

8 Promotion of 3R in demolition waste management 4.282 .617 8


4.259 .680 9

10 Estimation of demolition waste 4.213 .648 10


4.199 .475 11


4.190 .665 12

13 Planning the area for landfills 4.181 .610 13

14 Cost estimation of waste transport 4.176 .645 14

15 Choosing demolition methods 4.150 .588 15


4.125 .585 16


4.120 .582 17

18 Reduction of community disturbance during demolition stage

4.111 .732 18

19 Identifying rate of waste recovery 4.069 .594 19

20 Environmental Impact Assessment 4.056 .607 20

21 Planning the area for sorting platform 4.051 .634 21

22 Estimation of demolition cost 4.042 .612 22


4.032 .685 23

24 Planning storage space for recyclable materials 4.028 .510 24

The respondents’ perspective regarding the importance of stakeholders’ awareness and

training in improving DW management resonates with the study of Yuan, et al. (2011)

and Rao and Zhang (2015). In addition, it is found that identifying the environmental


issues and the DW characteristics, as well as DW volume prior to demolition work can

help decision makers plan effective DW management in urban redevelopment projects.

(Marzouk & Azab, 2014; Tam, 2008).

It is surprising to realise that although many social factors have been reflected as

important in urban redevelopment projects (Roussat, et al., 2009b; Yau & Ling Chan,

2008; Zheng, et al., 2014), the social decision-making factors were ranked fairly low in

the research survey in terms of their influences on DW management in urban

redevelopment projects. Only two of eight social factors were ranked as important, which

are ‘reduction of community disturbance during demolition stage’ and ‘preservation of

natural resources, cultural and heritage’ with mean values of 4.111 and 4.310

respectively. This result may be due to a lower importance placed on the role of

community in DW management in Vietnam in comparison to the delivery of urban


According to Spangenberg (2004), the institutional performance is one of the four major

aspects in achieving sustainability. In line with the ‘providing guidelines’ factor, four

other factors of this category were ranked at top-ten critical factors, such as ‘regular

information update’, ‘stakeholders’ responsibility’, ‘stakeholders’ roles in monitoring

and feedback’ and ‘understanding DW management procedures’. These results support

the stakeholders’ perspective that institutional factors play a vital role in influencing DW


This research uses Kendall’s coefficient of concordance to evaluate the extent to which

the participants scored the 24 decision-making factors upon a similar order. When the

concordance coefficient value closes to 1, the factors’ rankings are relatively identical.

By contrast, when the concordance coefficient value closes to 0, the factors’ ratings are

different (Yeung, Chan, Chan, & Li, 2007). In this research, the coefficient value was

0.063, greater than the recommended threshold of 0.05 as shown in Table 4-10, therefore,

it is concluded that the participants had statistically indifferent preferences when they

scored decision-making factors. The significant differences of respondents’ perspectives

in rating critical factors are further detected in the next sections.

Table 4-10: Kendall’s coefficient of concordance

N 216

107

Kendall's Wa .063

Chi-Square 313.333

df 23

Asymp. Sig. 0.001

4.5.6 Agreement on critical decision-making factors

The decision-making framework of urban redevelopment DW management is developed

based on the agreement of ranking decision-making factors by five groups of respondents.

In order to finalise the critical decision-making factors, the agreement should be analysed

in detail to gain a clear picture of the inter-relationship among five respondent groups.

Kruskal-Wallis was tested to identify whether there are significant differences in the

respondents’ rating of the level of importance.

This test showed that there was no significant difference in ranking of decision-making

factors between five groups, as shown in Table 4-11. It is indicated that five groups of

respondents had a consensus regarding the perceptions and expectation of urban

redevelopment DW management. In contrast, three critical factors, namely, ‘cost

estimation of waste transport’, ‘training of DW management’, and ‘the uniqueness of

DW’ have slight differences across five groups with p-value less than 0.05.

The significant differences between five respondent groups in Kruskal-Wallis test were

further validated by a correlational parametric test, which was one-way ANOVA test. The

results are shown in Table 4.12. These results were consistent with the results from

Kruskal-Wallis test. There were significant differences between five groups in the ranking

of three critical factors, namely, ‘cost estimation of waste transport’, ‘training of DW

management’, and ‘the uniqueness of DW’.

109

Table 4-11: Comparison of rating of critical decision-making factors for improving urban redevelopment DW management among key stakeholders


Deviation Rank G1 G2 G3 G4 G5

Kruskal-Wallis statistics (X2)

P-Value


4.444 .498 1 37.98 41.18 37.60 36.07 40.38 5.371 .251


4.412 .521 2 37.62 38.57 39.57 38.63 36.67 3.503 .477

3 Regular information update 4.398 .553 3 35.63 39.36 38.10 38.16 37.91 2.764 .598


4.384 .524 4 37.22 36.54 40.67 37.39 37.16 4.306 .366


4.329 .660 5 34.01 37.85 33.64 36.57 37.63 5.124 .275


4.310 .511 6 35.05 33.68 37.07 35.45 38.63 5.535 .237

7 Cost- effective demolition plan 4.306 .646 7 36.13 37.08 33.03 35.35 36.47 2.680 .613

8 Promotion of 3R in demolition waste management

4.282 .617 8 35.71 35.81 35.57 32.80 37.59 2.800 .592


4.259 .680 9 33.24 36.31 33.88 35.04 35.27 1.869 .760

10 Estimation of demolition waste 4.213 .648 10 31.53 36.30 36.22 33.87 32.45 4.040 .401


4.199 .475 11 32.93 34.69 32.84 33.92 34.16 2.469 .650


4.190 .665 12 35.26 34.26 37.48 29.39 31.74 8.087 .088



Deviation Rank G1 G2 G3 G4 G5

Kruskal-Wallis statistics (X2)

P-Value

13 Planning the area for landfills 4.181 .610 13 34.05 36.28 34.43 28.90 33.08 6.659 .155

14 Cost estimation of waste transport 4.176 .645 14 31.99 31.85 27.43 36.24 34.97 13.649 .009*

15 Choosing demolition method 4.150 .588 15 31.64 32.58 29.40 33.96 32.57 5.430 .246


4.125 .585 16 32.61 35.61 36.66 26.70 32.27 12.149 .016*


4.120 .582 17 33.64 29.64 25.53 32.65 36.23 19.292 .001*


4.111 .732 18 29.82 32.32 29.52 31.46 34.48 3.329 .504

19 Identifying rate of waste recovery 4.069 .594 19 33.11 31.05 31.67 27.39 33.23 5.146 .273

20 Environmental Impact Assessment 4.056 .607 20 32.29 30.82 33.74 27.15 31.78 5.202 .267

21 Planning the area for sorting platform 4.051 .634 21 33.04 30.86 32.53 28.75 28.02 5.228 .265

22 Estimation of demolition cost 4.042 .612 22 30.84 27.43 28.45 30.28 34.08 8.479 .076


4.032 .685 23 28.39 31.03 28.79 33.04 28.95 6.827 .145


4.028 .510 24 28.67 32.74 34.21 26.12 31.91 9.152 .057

Note: difference for Kruskal-Walllis test = 4

G1- Academic; G2 – Planner; G3- Consultant; G4- Engineer; G5 – Policy maker

P< 0.05: The mean difference among groups is statistically significant at the .05 level

111

Table 4-12: One-Way ANOVA statistic for log-transformed data of critical decision-making factors for improving urban redevelopment DW management

No. Factors Mean Std

Deviation Mean Square

Sig. (p-value)


.645 .0483 .003 .252


.642 .0516 .002 .568

3 Regular information update .640 .0561 .003 .437


.639 .0523 .002 .543


.631 .0703 .004 .479


.631 .0514 .005 .125

7 Cost- effective demolition plan .629 .0687 .003 .712


.627 .0652 .002 .799


.623 .0732 .002 .836

10 Estimation of demolition waste .620 .0697 .004 .532


.619 .0485 .001 .688


.616 .0732 .008 .186

13 Planning the area for landfills .616 .0655 .007 .144

14 Cost estimation of waste transport .615 .0697 .018 0.00*

15 Choosing demolition method .611 .0636 .005 .258


.611 .0633 .014 0.00*


.610 .0630 .020 0.00*


.607 .0806 .005 .597

19 Identifying rate of waste recovery .605 .0664 .007 .176

20 Environmental Impact Assessment .603 .0681 .005 .416

21 Planning the area for sorting platform .602 .0700 .005 .397

22 Estimation of demolition cost .601 .0688 .009 .101


.599 .0780 .010 .145


.597 .0563 .007 .061

Note: difference for One-Way ANOVA test = 4 G1- Academic; G2 – Planner; G3- Consultant; G4- Engineer; G5 – Policy maker P< 0.05: The mean difference among groups is statistically significant at the .05 level


Based on the results from both nonparametric and parametric analysis, the significant

differences of three critical factors were further detected by the Benjamini-Hochberg

procedure (presented in Chapter 3). This procedure was used to compute p-values

corrected for multiple comparisons in nonparametric Kruskal Wallis test, which was p-

corrected. The total of 24 sets of p-values was adjusted for multiple comparisons, which

corresponded to 24 critical factors as presented in Table 4-13.

Table 4-13: Adjusted differences based on p-value generated in Kruskal-Wallis test

No. Critical factors Mean Std.

Deviation Rank

p-value

p-rank

p-corrected

1 Training in the integrated waste management

4.120 .582 17 .001 1 0.010*

2 Cost estimation of waste transport 4.176 .645 14 .009 2 0.021*

3 Understanding the uniqueness of demolition waste

4.125 .585 16 .016 3 0.031*


4.028 .510 24 .057 4 0.042

5 Estimation of demolition cost 4.042 .612 22 .076 5 0.052


4.190 .665 12 .088 6 0.063

7 Training in demolition techniques 4.032 .685 23 .145 7 0.073

8 Planning the area for landfills 4.181 .610 13 .155 8 0.083


4.310 .511 6 .237 9 0.094

10 Choosing demolition method 4.150 .588 15 .246 10 0.104


4.444 .498 1 .251 11 0.115

12 Planning the area for sorting platform 4.051 .634 21 .265 12 0.125

13 Environmental Impact Assessment 4.056 .607 20 .267 13 0.135

14 Identifying rate of waste recovery 4.069 .594 19 .273 14 0.146


4.329 .660 5 .275 15 0.156


4.384 .524 4 .366 16 0.167

17 Estimation of demolition waste 4.213 .648 10 .401 17 0.177


4.412 .521 2 .477 18 0.188

19 Reduction of community disturbance during demolition

4.111 .732 18 .504 19 0.198


4.282 .617 8 .592 20 0.208

21 Regular information update 4.398 .553 3 .598 21 0.219 22 Cost- effective demolition plan 4.306 .646 7 .613 22 0.229


4.199 .475 11 .650 23 0.240


4.259 .680 9 .760 24 0.250

113

In this test, p-corrected = where i is the rank of ascending input p-values (p-rank); m

is the total number of tests (m=24); and Q is critical value for a false discovery rate

(q=0.25). The significant difference that was detected when the largest of p-value is less

than the p-corrected was ‘the uniqueness of DW’ factor, where the p-value (0.016) was

less than p-corrected (0.031). Thus, the first three tests were significant because the p-

value was less than that of ‘the uniqueness of DW’ factor and also less than p-corrected.

Accordingly, the three critical factors that were deemed truly significant, namely,

‘training of DW management’, ‘cost estimation of waste transport’, and ‘the uniqueness

of DW’ with p-corrected, were 0.010, 0.021, and 0.031 respectively.

These critical factors further detected the differences between two independent groups by

using the nonparametric test, which was Mann-Whitney test (Table 4-14). The test

revealed that there were significant differences between consultants (G3) and two other

groups: engineers (G4) and policy makers (G5) as regards the factor of ‘training of DW

management’. On the other hand, consultants are deemed to have more attention to this

critical factor (training of DW management) than academics. In addition, the planner

group was also identified to have a different perspective compared to the policy maker

group in training of DW management. This may be due to the fact that engineers and

policy makers considered the need of training in DW management, while the other three

groups (academics, planners, and consultants) thought that the local authority and the

government should provide contractors with the courses of DW management knowledge

often.

The Mann-Whitney test also divulged that planners (G2) in the research's respondents

had different perspectives on the significance level of the ‘cost estimation of waste

transport’ compared to the engineers (G4). This is possible because planners are not much

concerned about the cost of waste transport. In addition, significant differences in the

rating factor of ‘cost estimation of waste transport’ also existed between consultants (G3)

and two other stakeholder groups: engineers (G4) and policy makers (G5). It seems that

consultants worry less about ‘cost estimation of waste transport’ as they mainly get

involved in the environmental issues.


The rating of ‘the uniqueness of DW’ also revealed the significant differences between

engineers (G4) and three other stakeholder groups: academics (G1), planners (G2) and

consultants (G3). It is believed that engineers tend to focus more on technical factors

rather than understanding the characteristics of DW. This might be related to the

insufficient knowledge of DW management, in which all stakeholders involved in DW

management process need to be equipped.

Table 4-14: Probability values in Mann-Whitney test on three critical factors

Comparison between groups of stakeholders

Mann-Whitney test results (p-value)

Training the human resources in the integrated waste management

Cost estimation of waste transport

Understanding the uniqueness of demolition waste before demolition stage

G1/G2 0.062 0.642 0.356

G1/G3 .001* 0.092 0.23

G1/G4 0.994 0.062 .032*

G1/G5 0.289 0.524 0.84

G2/G3 0.126 0.168 0.672

G2/G4 0.063 .017* .004*

G2/G5 .012* 0.242 0.341

G3/G4 .001* .001* .004*

G3/G5 .001* .019* 0.245

Note: * The probability value is significant at 0.05 level (2-tailed) G1- Academics; G2 - Planners; G3- Consultants; G4- Engineers; G5 - Policy makers

The Mann-Whitney test results above suggested that the three critical factors can be

statistically regarded as important to urban redevelopment DW management. The

respondents with different backgrounds and responsibilities may have different

perceptions about the factors affecting decision-making of urban redevelopment DW

management. Hence, the factors identified and rated as critical will act as a sound

foundation upon which the decision-making framework for urban redevelopment DW

management can be based.

The findings from Mann-Whitney test were further validated by a correlational

parametric test, which was 2-sample t test. The results are shown in Table 4.15. These

results were consistent with the results from Mann-Whitney test.

115

Table 4-15: Probability values in 2-sample t test on three critical factors

Comparison between groups of

stakeholders

2-sample t test results (p-value)


Cost estimation of waste transport


G1/G2 .055 .782 .246

G1/G3 .001* .093 .226

G1/G4 .955 .059 .025*

G1/G5 .390 .381 .652

G2/G3 .125 .145 .811

G2/G4 .060 .018* .002*

G2/G5 .015* .233 .165

G3/G4 .001* .000* .004*

G3/G5 .000* .011* .170

G4/G5 .360 .232 .134

Note: * The probability value is significant at 0.05 level (2-tailed) G1- Academics; G2 - Planners; G3- Consultants; G4- Engineers; G5 - Policy makers

However, the significant differences of the above three critical factors were further

detected by the Benjamini-Hochberg procedure. This made it possible to adjust the

different perspectives about the three critical factors mentioned above, across five groups

of stakeholders. Three sets of p-values of the three stated critical factors in Mann Whitney

test were adjusted for multiple comparisons and each set comprised of 10 tests

corresponding to each pair in five stakeholder groups. Table 4-16 presents the results of

adjusting p-values generated in the Mann-Whitney test by the Benjamini-Hochberg

procedure.

In this test, p-corrected = where i is the rank of ascending input p-values (p-rank); m

is the total number of tests (m=10); and Q is critical value for a false discovery rate

(q=0.25). Regarding the factor of ‘training of DW management’, after adjusting p-values,

using the Benjamini-Hochberg correction, the different perspectives between planners

(G2) and policy makers (G5), as well as the differences between consultants (G3) and

two other groups: engineers (G4) and policy makers (G5) were verified as discussed in

the previous section.


Table 4-16: Adjusted differences based on p-value generated in Mann-Whitney test

No Comparison

between groups of stakeholders

1. Training the human resources in the integrated waste

management

2. Cost estimation of waste transport

3. Understanding the uniqueness of demolition waste before

demolition stage

p-value p-rank p-corrected p-value p-rank p-corrected p-value p-rank p-corrected

1 G1/G2 .062 5 .125** .642 10 .250 .356 8 .200

2 G1/G3 .001* 2 .050** .092 5 .125** .230 5 .125

3 G1/G4 .994 10 .250 .062 4 .100** .032* 3 .075**

4 G1/G5 .289 9 .225 .524 9 .225 .840 10 .250

5 G2/G3 .126 7 .175** .168 6 .150 .672 9 .225

6 G2/G4 .063 6 .150** .017* 2 .050** .004* 1 .025**

7 G2/G5 .012* 4 .100** .242 8 .200 .341 7 .175

8 G3/G4 .001* 3 .075** .001* 1 .025** .004* 2 .050**

9 G3/G5 .000* 1 .025** .019* 3 .075** .245 6 .150

10 G4/G5 .283 8 .200 .200 7 .175 .111 4 .100

Note: * The probability value is significant at 0.05 level (2-tailed)

** The adjusted probability is significant at p-value <p-corrected

G1- Academics; G2 - Planners; G3- Consultants; G4- Engineers; G5 - Policy makers

117

In addition, the significant differences that were revealed between academics (G1) and

two other groups, planners (G2) and consultants (G3) with p-corrected were 0.125 and

0.050 respectively, and between planners (G2) and two other groups, consultants (G3)

and engineers (G4) with p-corrected were 0.175 and 0.150 respectively. There is a

possibility that academics and planners are involved in the early stage of DW

management process, which is contrary to the other groups playing their roles in the

demolition stage.

Similarly, the significant differences between academics (G1) and two other groups,

consultants (G3) and engineers (G4) as regards to the factor of ‘cost estimation of

waste transport’ that were further detected significant with p-corrected were 0.125 and

0.100 respectively. It is believed that academics have a low level of concern about

cost-effectiveness compared to consultants and engineers, who directly work with the

DW management plan. On the other hand, the p-corrected values from sets of ‘the

uniqueness of DW’ were verified with the results of the Mann-Whitney test, which

was discussed in the previous section.

The above three critical factors (training of waste management, cost estimation of

waste transport, and the uniqueness of DW) existed the significant differences might

all contribute to the latent conflicts hindering the stakeholders’ interactions in urban

redevelopment DW management. These are verified in the interview study and should

be further addressed in future research.

4.6 MAIN FINDINGS OF THE QUESTIONNAIRE SURVEY

4.6.1 Main findings

The questionnaire survey results of this research highlight the following points with

regard to improving decision-making of urban redevelopment DW management:

The respondents selected 24 out of 53 decision-making factors as the critical decision-

making factors, which are presented in Table 4.9.

The critical factors represent a set of decision-making factors that are important in

improving urban redevelopment DW management. These factors have been voted

based on five categories, namely, technical performance, environmental performance,


economic performance, social performance, and institutional performance, which are

all sustainable aspects.

The decision-making framework formulated on the basis of the critical factors will

assist decision makers in making the right decisions to improve urban redevelopment

DW management practices.

There were no additional factors identified by the respondents, which proved that the

questionnaire comprehensively encompassed relevant factors identified from reviews

of the previous literature.

According to the respondents’ background and roles, there are similarities among the

five groups of respondents in the ratings of the level of importance of potential

decision-making factors. The top five ranked decision-making factors received a

perception consensus of all groups in ‘guidelines of DW management’, ‘on-site

sorting’, ‘information update’, ‘determining the procedure’, and ‘stakeholders’

responsibility’. On the other hand, there were some differences in the ranking of the

level of importance for decision-making factors. This could be seen in the rating of

factors in the two categories of economic performance (‘cost estimation of waste

transport’), and environmental performance (‘the uniqueness of DW’ and ‘training of

waste management’). These factors were verified in the next chapter, interview study.

The performances of technique, environmental and institutional, significantly

influence the decision-making of urban redevelopment DW management, with 19 out

of 24 critical factors identified.

4.6.2 Revised conceptual framework

Based on the questionnaire survey results and the findings, the conceptual decision-

making framework is developed, as shown in figure 4-2. The critical decision-making

factors are grouped into five categories: technical, environmental, economic, social

and institutional. This conceptual framework was further investigated through the

interviews. In addition, a GIS-based model is developed based on case study, to

establish the decision support system for the decision-making framework.

119

4.7 SUMMARY

This chapter detailed the results and findings of the survey study. The findings in this

chapter answered the first research question: What are the key decision-making factors

influencing demolition waste management in Vietnamese urban redevelopment

projects?

The survey identified 24 decision-making factors based on their importance assesses

by five groups of stakeholders. The findings show that the technical, environmental

and institutional performances significantly influence the decision-making process of

urban redevelopment DW management. Based on the current DW management

performance in Vietnamese urban redevelopment projects, the 24 critical decision-

making factors were encapsulated into a revised conceptual framework. These critical

decision-making factors were further discussed by the interviewees in the interview

Choosing demolition method

DW management procedures

Waste classification and estimation

Planning for landfill, sorting area, and storage

Training


The uniqueness of DW

3R strategies and recovery

Environmental Impact Assessment

Cost-effectiveness plan

Cost estimation for demolition and DW transport

Preservation

Reduction of disturbance

Best practice guidelines


Information and communication

Technical

Environmental

Influencing

factors of

demolition waste

management

decision-making

in Vietnamese

urban

redevelopment

projects

Economic

Social

Institutional

Figure 4-2: Revised conceptual framework for improving decision-making in DW management for urban redevelopment projects


study as presented in Chapter 5. Subsequently, the conceptual framework was also

refined in the interview stage.

121

Chapter 5: Interview

5.1 INTRODUCTION

The questionnaire survey results have refined the conceptual decision-making

framework for improving urban redevelopment DW management in Vietnam, which

has been clearly explained in the previous chapter. The conceptual decision-making

framework was then introduced and validated by key stakeholders in the stage of semi-

structured interviews and also involved the identification of action plans in response

to the revised decision-making framework. The other purpose of the interviews was to

identify the current practice, problems, and action plans regarding the critical decision-

making factors in improving urban redevelopment DW management in Vietnam. This

chapter first outlines the participant selection process and the participants’

background. It subsequently explains the use of interview instruments in the research.

Then, an explanation of how the data collected was interpreted and analysed is

described before the interview discussions are presented. This is followed by the main

findings of the interview study and finally, the interview results and findings are

summarised in the last section of the chapter.

5.2 INTERVIEWEES’ SELECTION AND THEIR BACKGROUND

5.2.1 Selection of interviewees

The selection of participants in the interview was conducted in order to obtain a good

representation of the organisations with regard to urban redevelopment DW

management in the three main cities in Vietnam, namely Hanoi, Hai Phong, and Ho

Chi Minh cities. In addition, the interviewees were selected based on their,

background, experience, current positions and availability for the interview, which

described in Chapter 3, Section 3.6.3. This is to ensure that the objectives of the

interviews can be achieved. Based on the questionnaire survey, 29 survey respondents

who expressed interest in participating in the interview were approached. Of these 29

participants, 22 interviewees were selected to participate in the interview, comprising

four academics, three planners, three consultants, six engineers, and six policy makers.

A total of 22 interviews were conducted from April to June 2017.

122 Chapter 5: Interview

Similar to the questionnaire participants, the interviewees represented five key

stakeholder groups. Among the 22 interviewees, four were researchers, three were

planners, three were consultants, six were engineers and six were policy makers. Out

of 22 respondents, 12 held relatively high positions in their organisations. Most of the

respondents were from Hanoi. This is because Hanoi is leading in urban

redevelopment activities in Vietnam and the organisations related to urban

redevelopment DW management are mainly located in Hanoi. The statistical

breakdown of interviewees can be seen in Table 5-1.

Table 5-1: Statistical Breakdown of Interviewees

Interviewee type Number of interviewees

By profession Academic 4

Planner 3

Consultant 3

Engineer 6

Policy maker 6

By executive level Manager/Director 12

Other 10

By geographical spread Hanoi 15

Hai Phong 3

Ho Chi Minh City 4

5.2.2 Interviewee background

In order to achieve the interview’s objective, the selected interviewees need to have

the capability to provide robust knowledge and extensive experience regarding urban

redevelopment DW management in Vietnam. In addition, their organisations play an

important role in the decision-making process in related fields. A summary of the

interviewees’ profile is presented in Table 5-2. All of the interviewees had more than

10 years of experience. Most of them held key positions in the projects such as

directors, decision makers, on-site managers, and environment managers. Thus, the

information, insights, and suggestions provided by the interviewees would be reliable

to help better interpret the critical decision-making factors from the questionnaire

survey.

123

Table 5-2: Interviewee Profiles

Respondent Organisation characteristic

Role in Project Experience (years)

Interview mode

R1 Government Director Decision maker 22 Face to face

R2 Government Decision maker 15 Face to face

R3 Government Associate Director/planner

18 Face to face

R4 Waste management contractor

Engineering Manager 10 Telephone

R5 Government Decision Maker 13 Face to face

R6 Government Associate Director/Planner

15 Face to face

R7 Local Authority Project Engineering manager

20 Face to face

R8 Academic Project Consultant 20 Face to face

R9 Academic Environmental Expert/Consultant

10 Face to face

R10 Construction contractor

On-site manager 17 Telephone

R11 Academic Technical Expert/Consultant

12 Face to face

R12 Local Authority Planner 15 Face to face

R13 Government Academic 15 Face to face

R14 Government Academic 14 Face to face

R15 Government Environment Manager/Academic

17 Telephone


On-site Manager 17 Telephone

R17 Local Authority Policy Maker 15 Telephone

R18 Academic Waste management Expert

20 Face to face

R19 Government Engineering Manager/Policy maker

21 Telephone

R20 Local Authority Senior Manager/Policy maker

20 Telephone


On-site Manager 17 Face to face

R22 Waste management contractor

Engineering Manager 18 Telephone


5.3 INTERVIEW INSTRUMENTS

As discussed, the survey results that were drawn from in-depth interviews helped

interpret and elaborate on the critical decision-making factors. Before executing the

interview section, several processes are involved. Each interviewee was contacted

through email or by phone for an appointment. Interviewees were electronically

provided with the following information for better preparation.

A cover letter (Appendix C)

Information consent form for QUT research project

Interview question sheet (Table 5-3)

Conceptual framework (Figure 4-2)

Due to restrictions of locality and budget, two options for conducting the interviews

were chosen: either face to face or over the telephone. Out of 15 interviewees, 14 from

Hanoi participated in the face-to-face interviews. Eight interviews were conducted by

phone, with one interviewee from Hanoi, four interviewees from Ho Chi Minh and

three interviewees from Hai Phong.

The interview duration generally lasted from 35 to 65 minutes. Out of consideration

for privacy and ethical protection, all interviewees were promised complete

confidentiality regarding the data provided by them when transcribed. With the

interviewees’ consent, most of the interviews were recorded, and only two of the

interviewees did not allow their conversation to be recorded. Thus, the note-taking

method was applied to obtain the information from these two interviews.

5.4 INTERVIEW FORMAT AND STRUCTURE

The interview questions were designed based on the result of the questionnaire survey.

Five major questions were formulated with sub-questions provided in Table 5-3. The

questions were qualitative in nature, which allowed the interviewees to comment and

state their insights and experience on issues related to critical factors.

There were 15 main theme questions, which were grouped based on 24 critical

decision-making factors. In order to obtain the interview objective, four major

questions and four sub-questions were designed to discuss across 15 themes. As the

interview format is semi-structured, the interview questions could be open-ended and

altered.

125

Table 5-3: Interview questions

No. Theme Major questions Sub-Questions

1 Choosing demolition methods 1. Comment on the significant influence of critical decision-making factors of urban redevelopment DW management in Vietnam (Strengths and Weaknesses)

2. Comment on related policies and strategies of urban redevelopment DW management in Vietnam.

3. Comment on the challenges and opportunities that might be faced as a result of critical factors in the context of Vietnam.

4. Other points regarding urban redevelopment DW management that are missing from the interview

‐ What are the elements supporting factors?

‐ What could be improved?

‐ What adaptive actions can you offer to tackle the challenges?

‐ What other factors do you believe affect the decision-making of urban redevelopment DW management?

2 Determining demolition waste management procedures

3 Waste classification and estimation

4 Planning for landfill, sorting area, and storage

5

Training

• Demolition technique training • Waste management training

6 Stakeholders’ awareness

7 Uniqueness (types, characteristics of DW)

8

3R strategies and recovery

• Promotion of 3R • Rate of recovery

9 Environmental Impact Assessment

10

Cost estimation and cost-effectiveness

• Cost estimation of waste transport

• Cost estimation of demolition work

• Cost-effective demolition plans

11 Preservation (Prevention of natural resource, cultural and heritage)

12 Reduction of community disturbance

13 Best practice guidelines

14


• Stakeholder responsibility • Stakeholders’ role in monitoring

and feedback

15 Information and communication (Regular information update)


According to Adams, et al. (2007) and Berg (2004), in order to obtain the valuable

information in the interview, a pilot interview needs to be conducted with the experts.

The interview questions were pre-tested with two academics and one practitioner to

ensure the suitability and comprehensibility of questions, especially in the context of

Vietnam. Minor alterations were made as a result of this pre-test. In order to ensure

the interviewees had a common understanding of each critical factor and theme, the

explanation was given before the interview took place.

5.5 INTERVIEW RESULTS AND DISCUSSION

The interview results are described based on the main themes listed above. In order to

analyse the interview data, content analysis was applied as an inductive approach.

Content analysis is a popular technique of both quantitative and qualitative data

analysis, which helps researchers to achieve research objectives (Adams, et al., 2007).

The purpose of the content analysis is to illustrate the content of the interviewees’

recommendations and to categorise the various expressed opinions. The interview

contents were categorised in 15 main themes and are analysed in the following section.

5.5.1 Choosing demolition methods

Choosing appropriate demolition methods is in relation to making decisions of DW

management. In this theme, seven interviewees (one academic, one planner, one

engineer, and four policy makers) held the belief that choosing demolition technology

is very important to DW management (R3, R4, R5, R14, R17, R19 and R22). One

engineering manager emphasised that technology leads to reduction of DW and

improvement of the waste classification (R22). However, two policy makers claimed

that the construction contractors may be reluctant to employ the best technology as it

is costly, and further training for workers is needed (R5, R19). A suggestion by one

policy maker is that the government should formulate the policy in encouraging and

enforcing the use of environmentally friendly technology (R5). This is in line with the

argument of Yeheyis, Hewage, Alam, Eskicioglu, and Sadiq (2013) that the rate of

reuse and recycling of C&D waste is mainly dependent on the demolition method

employed to remove materials from a structure, and the studies by Lu and Yuan (2010)

and (Wang & Yuan, 2008), which revealed that construction technology contributes

significantly to the reduction, reuse and recycling of C&D waste.

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It is noteworthy that the construction industry is considered as a major polluter, that

should devise effective construction waste management plans with the efficiencies in

the environment and economic performances (Mcdonald & Smithers, 1998). This was

expressed by one local authority policy maker interviewee as follows:

‘There are different methods of dismantling the old buildings; however, it is

important to consider demolition methods for cost-effectiveness’ (R17).

5.5.2 Demolition waste management procedures

The survey results reflect that the procedures of the demolition process are considered

as an important factor influencing DW management decision-making. Seven

interviewees (one academic, three planners and three engineers) agreed that the

procedures and practices for each stage need to be clearly defined (R3, R6, R7, R10,

R12, R13, and R16). One governmental planner emphasised that ‘determining the

procedures is very important in helping stakeholders to manage time effectively,

minimise problems during demolition work and increase the rate of waste recovery’

(R6). This resonates with Poon, et al. (2001) in that an effective on-site C&D waste

management often involves the plan of different stages of waste management, from

clearance, collection, transport, and disposal. Thus, the need for a detailed and

comprehensive plan of C&D waste management in conducting the construction project

is to achieve waste minimisation and a high level of recycling waste (Yeheyis, et al.,

2013; Yuan, 2013). In Hong Kong, a waste management plan is required for all

construction projects from 2003 (Tam, 2008). On the other hand, in Vietnam, the

consensus among the interviewees is that urban redevelopment projects usually lack

the site procedure scheduling for DW management and delivery planning of DW. One

engineer, as an on-site manager, claimed that ‘the lack of DW management plan leads

to the ineffective DW management and low recovery rate in Vietnamese urban

redevelopment projects’ (R10). In addition, one academic suggested that

‘The procedures of demolition and demolition waste management are to be

clearly identified to make the right decisions. These should be early developed

before demolition work is undertaken by project managers’ (R13).

In order to determine the DW management procedures, interviewees proposed

solutions, including developing the DW management plan in the early stage before


demolition work, formulating the policy on environmentally friendly technology, and

considering the cost-effectiveness of demolition methods.

5.5.3 Waste classification and estimation

This theme includes the decision-making factors of on-site sorting and waste

estimation. On-site sorting/separating of DW is essential to the effectiveness of DW

management. This, together with the factor of waste estimation, receives scrupulous

attention from respondents in the questionnaire survey.

According to Wu and Ann (2014), on-site sorting that is effectively implemented

would assist contractors in arranging and using materials properly. In addition, through

this strategy, contractors can increase the value of recyclable waste and avoid the

pollution of mixed materials. In fact, four interviewees (one consultant, two engineers

and one policy maker) complained that the main issues of C&D management in

Vietnam are the lack of on-site sorting practice and the fact that most of the C&D

waste generated in construction projects is mixed and even is disposed together with

municipal solid waste (R2, R11, R16, R17). In addition, one engineer reflected that

‘there is a poor classification of DW, especially DW generated in urban redevelopment

projects in Vietnam’ (R21). As a result, one academic from the government agency

reported that ‘resource recovery was less effective, which leads to the low rate of waste

recovery in Vietnam compared to developed countries’ (R13).

The study by Poon, et al. (2001) reported that there is a need for decomposing the

C&D waste into its components before delivery, for example into inert and non-inert

materials. This offers the separation sources advantages in terms of less effort required

and better segregation waste types, compared to off-site classification. However, Poon,

et al. (2001) also indicate that the construction industry in Hong Kong is reluctant to

conduct on-site waste classification and still has little incentive to implement on-site

classification. Three interviewees (two academics and one policy maker) were in

agreement that it is necessary to make the stakeholders aware of DW management by

participating in on-site sorting (R13, R14, R20). One engineer as a waste management

contractor put forward a suggestion for improving DW management:

‘Classification of demolition waste would require a priority for improvement

of demolition waste management by stakeholders involved in urban

redevelopment projects in Vietnam’ (R4).

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According to Formoso, et al. (2002), waste estimations are more supportive to the

management process for the cause of enabling operational cost and information of

waste generation, which is useful for managers in controlling projects. Most of the

interviewees were in agreement with the significance of waste estimation in decision-

making of urban redevelopment DW management. One policy maker as the director

of a government agency emphasised that ‘the regulation on C&D waste management

(the circular 08/2017/TT-BXD) will be effectively implemented when the volume and

type of C&D waste of the waste stream are clearly understood’ (R1). This requires the

estimation of waste in construction projects and an interviewee as one planner from

the local authority suggested that ‘demolition waste estimation should be scheduled in

early stages as this information can help decision makers have right decisions of cost

and time effectiveness’. He provided an example that ‘based on waste estimation, the

contractors can estimate the number of trucks for waste transport and identify the

appropriate waste destinations’ (R12).

This theme helped obtain valuable suggestions from interviewees, including raising

awareness of on-site waste sorting, prioritising the waste classification to improve DW

management and increase the recovery rate, and estimating DW in the planning stage.

5.5.4 Planning for landfill, sorting area, and storage

Planning for waste management refers to planning of sorting platform, landfills for

waste disposal, and transfer station for recyclable DW. It is understandable that in view

of WM, the planning of WM from generation, collection and disposal enhances

effective DW management in a number of ways, such as increasing the recovery rate,

reducing cost and time of waste transport and remedying the impacts of DW on the

environment.

Three interviewees (two planners and one policy maker) reported that there is limited

landfill for C&D waste in Vietnam (R3, R6, R19). For example, ‘three out of five

landfill planning for the C&D waste disposal were full in 2012, namely Van Noi, Vinh

Quynh, and Dan Phuong’, one government planner reflected. With the speed of the

development in Vietnam, the C&D waste is predicted to increase sharply. In

consideration of limited landfills and the increase in C&D waste, four interviewees

(one planer, one consultant, one engineer, and one policy maker) agreed that planning

of the landfills should be given priority (R6, R9, R10, and R19). The same scenario is


found in Shenzhen, China, where there have been limited C&D waste landfills from

2010 (Lu, et al., 2011). Lu, et al. (2011) also claimed that the planning of new landfills

by the government was far behind, as only one landfill was fully built in the strategy

between 2006 and 2010. In addition, Wong and Yip (2004) state that the Hong Kong

government searched for landfill spaces for C&D waste from 2016 to 2045, due to

running out of landfill spaces in 2015 and the lack of reclamation sites.

The study by Yuan (2013) reveals that consideration of systematically planning waste

recycling facilities based on transportation distances throughout the region can save

the waste transportation cost and heighten the contractors’ awareness of sending waste

to recycling facilities because of the convenience in transportation. However, in

Vietnam, little attention has been paid to planning recycling material storages or

transfer stations. Three interviewees (one planner, one consultant, and one policy

maker) stated that this may be due to the neglect of recyclable construction materials

(R5, R6, R9). In order to reduce the cost and time of waste transport and increase the

recovery rate, one government planner claimed that

‘the issues of C&D transport and disposal need to be addressed by promoting

the planning of waste storages, waste transfer stations and specific waste

landfills for construction and demolition waste’ (R6).

This is in line with the statement by Rao, Jha, and Misra (2007) that the long distance

involved in waste transport to the recycling facilities is uneconomical C&D waste

management. This can be set up close to a demolition site. In addition, planning the

optimal transfer stations and landfills should be based on the status of land-use and the

transportation network. Three interviewees (one planner and two engineers) were in

agreement that proper planning will result in effective management of DW by saving

time and cost for waste storages, waste transportation and waste disposal (R12, R16,

and R22). One planner from the local authority claimed that ‘it is pivotal to consider

which place is more suitable for transfer station or waste disposal in DW management

plan’ (R12).

Three interviewees (one academic and two planners) also pointed out that the

increasing trend of urban redevelopment in some cities in Vietnam will generate a huge

amount of DW, which calls for a need to plan a suitable site for recycled waste and

disposal waste at a large level (R3, R12, R18). One engineer as a construction

contractor reflected that ‘in Vietnam, DW is mainly used for land reclamation and site

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formation’ and he suggested that ‘there is the need of further research into the use of

DW in road sub-based’ (R10). In supporting the site identification for DW

management, one engineer as on-site manager emphasised that ‘economic

development plan and land-use should be considered in landfill selection. In addition,

the cost-effective comparison should be taken into account for choosing the suitable

sites’ (R21).

The highlights of this theme were discussed by interviewees including prioritising

C&D waste planning, promoting the use of DW in road sub-base, and identifying the

suitable sites for transfer stations and landfill.

5.5.5 Training

Training the human resource and skilled personnel involves the decision-making

process that affects effective DW management. In support of this theme, many studies

revealed that the C&D waste generation is substantially affected by skilled

construction workers (Lu & Yuan, 2010; Tam & Tam, 2008; Wang & Yuan, 2008).

Wang and Yuan (2006) also state that one of the problems associated with construction

waste management is the lack of sufficient waste management skills. Three

interviewees (one academic, one consultant, and one policy maker) asserted that

sufficient training for the workforce involved in DW management is the most

important, raising the workforce’s awareness about DW management and the use of

advanced technology in waste classification (R2, R6, R15). One academic consultant

voiced that

‘The limited knowledge of demolition work and waste management may lead

to problems related to the low rate of waste recovery and increased cost of

waste management’ (R11).

In addition, one policy maker from a government agency proclaimed that ‘in order to

ensure safety in the demolition process and minimise the impacts of this process on

the environment and community, the personal skills of on-site workers need to be

trained’(R5). For example, through vocational training, workers can promote waste

minimisation, the policy maker added (R5). This resonates with a study by Wu and

Ann (2014), in that education and training are important to waste minimisation. In

reality, the amount of waste is increased due to the unawareness of its impact of the

environment and the construction workers can efficiently work with less waste if they


are trained to deploy material tools in advance. Another two academics also agreed

that the technical factors influencing DW management are likely related to a lack of

technical personnel skills among stakeholders (R11 and R18). In Vietnam, most of the

construction workers may not be sufficiently trained about environmental protection,

waste management, or low waste technologies. Therefore, one of seven policy makers

suggested that ‘the capacity of key stakeholders in waste management and dismantling

process needs to be built and project managers should arrange time for training before

the implementation of projects’ (R2).

It was suggested by the interviewees that training is important to DW management, as

it can minimise waste generation and help in waste classification. Training in the early

stage, especially on-site skill training, can remedy the impacts on the environment and

the community.

5.5.6 Stakeholder awareness

Awareness refers to the willingness of DW management by stakeholders. Several

studies revealed that the practitioners’ perspective on resource saving, environmental

protection, is a vital factor of C&D waste minimisation, by changing their attitude

toward waste generation, classification, recycling and disposal (Manowong, 2012;

Osmani, Glass, & Price, 2008).

Two out of six engineers (R10, R16) discerned that the efficiency of DW management

depends on the awareness of stakeholders on classification of DW, waste recycling

and waste disposal. However, they reflected that the construction contractors have had

little awareness of DW management, as they perceived that it increases a project’s cost

and time and their company may lose benefits in equipment, training and waste

transport. This is in line with the research by Wong and Yip (2004), which revealed

that in Hong Kong, almost all of the contractors were indeed aware of the significance

of sustainable C&D waste management but they did not properly implement

environmental measures, and have been working for profits and survival. In addition,

the research by Poon, et al. (2001) and Yuan (2013), state that the environmental issues

including C&D waste management are not given priority in construction projects.

Three interviewees (one engineer and two policy makers) suggested that it is a

requirement to leverage the understanding about DW management by training,

promulgating C&D waste policies, and participating in on-site sorting (R2, R17, R21).

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Interestingly, one consultant recognised the role of governments in raising

stakeholders’ awareness about sound DW management in urban redevelopment

projects:

‘This should be changed initially by key stakeholders and leaders in the

influential government agencies. The government should organise and sponsor

training programs with regard to DW management’ (R8).

This is consistent with findings by Wu and Ann (2014), that the contractors have

neutral environmental awareness as implementing C&D waste management would be

costly. Wu and Ann (2014) conclude that the government must place sustainability in

regional development because it has a high level of willingness in implementing C&D

waste management.

It is discussed that the DW management is affected by stakeholders’ awareness. There

is a need for raising their willingness by training, promulgating C&D waste policies,

and participating in on-site sorting, in which the government should play a key

leadership role.

5.5.7 The uniqueness of demolition waste

Understanding the nature of DW is essential for implementing effective DW

management. This is clearly expressed by stakeholders in the decision-making process.

Three interviewees (two academics and one policy maker) were in agreement that in

the next two decades, there will be large-scale urban redevelopment activities in

Vietnam, and it is predicted that there will be an overwhelming amount of DW

generation, such as in Hanoi and Ho Chi Minh City (R5, R8, R9). One engineer

interviewee, as the construction contractor, reflected that ‘the main proportions of DW

are bricks and mortar with low rate of cement because almost all of the buildings are

aged about 30 to 50 years’ (R10). This resonates with the study by Poon (1997), that

masonry, wood, concrete and brick typically produced more than half of DW

management.

One academic interviewee from the government agency affirmed that ‘the quality of

demolition waste is not suitable for the recycling purpose of construction materials,

such as concrete because the characteristics of demolition waste present a low

potential of recycling compared to waste from new construction’, and he suggested


that ‘there is the need of investigation the DW characteristics in the early stage to

assist decision makers in effective DW management’ (R15). This is in line with the

research of Kofoworola and Gheewala (2009), in that the inventory of C&D waste

generation should be implemented, which provides useful information for recycling

waste strategy.

5.5.8 “3R” strategies and recovery

The survey results show ‘3R’ principles and waste recovery are the key decision-

making factors of DW management. Three interviewees (two policy makers and one

planner) were in agreement that the promotion of 3R strategies in urban redevelopment

DW management can increase the waste recovery rate and minimise waste volumes to

the landfills (R1, R4, R7). This resonates with the study by Yeheyis, et al. (2013), in

that reuse and recycle of C&D waste are the challenges to management of a large

amount of waste in achieving sustainable construction for a better environment. This

offers benefits in terms of reducing the use of raw materials and converting more

recyclables from the landfills (Abbas et al., 2006). However, one government

academic and one local authority planner alleged that in Vietnam, 3R strategy is often

neglected by contractors for many reasons, such as the lack of stakeholders’ awareness,

poor waste management plans and the lack of application of low waste technologies

(R12, R13). In addition, one policy maker as senior manager perceived that ‘there is

lack of incentive policy to encourage the focus on waste conversion in Vietnam’ (R20).

This is in line with the issue in Shenzhen, China, where there is unclear regulation to

support the strategies of reduction and recycling, or such regulations are hard, to a

certain extent, to follow (Yuan, 2013).

One policy maker from the local authority reported that ‘the government have just

enacted the circular 08/2017/TT-BXD about C&D waste management in May 2017,

which will be a concrete foundation for regulation related to the development of 3R

strategies’ (R17). In order to promote 3R in DW management, one academic

consultant interviewee suggested that

‘3R strategies should be regulated in C&D waste management in Vietnam and

encouraged at the source by economic intensive programs and recycling

market development’ (R18).

135

Regarding the recovery rate of DW, one academic and one policy maker asserted that

effective urban redevelopment DW management in Vietnam is of great importance for

the purpose of increasing recovery rate (R8, R19). In addition, the policy maker

maintained that ‘this is because the amount of DW in the urban redevelopment projects

are foreseen to constitute a high quantity of C&D waste in some major cities in

Vietnam and the running out of C&D waste landfills is likely in the future’ (R19). This

is supported by Hendriks and Jansen (2001), who stated that C&D waste is considered

as secondary raw material that should be strongly encouraged by the authorities and

by the construction industry because of facing due to the possibility of rising waste

disposal fees and the limitations on the exploration of primary raw material. One policy

maker interviewee, as a local authority, emphasised the use of DW as secondary

materials: ‘the government should plan effectively the use of recycled material, such

as providing more details of demolition waste composition’ (R20).

In addition, one government planner stressed that ‘in order to ensure the increased

recovery rate, the stakeholders should consider not only the 3R strategies but also the

demolition technologies and waste onsite-classification’ (R6).

Interviewees provided valuable suggestions for the purpose of better 3R adaptation

and increased recovery rate, including promoting 3R in C&D waste management by

economic intensive programs and recycling market development, and increasing the

waste recovery rate based on 3R strategies, demolition technologies, and on-site

sorting.

5.5.9 Environmental impact assessment

Environmental impact assessment is vital to conform to urban redevelopment DW

management projects to environmental safety and thereby ensure sustainable

economic development. The consensus among the interviewees is that this principle is

regulated in Vietnam’s law on environmental protection and it is obligated in

development projects. However, one policy maker as senior manager claimed that ‘the

regulation of environmental impact assessment is ineffectively implemented’ (R20).

This resonates with the study by Yeung (2008), which expounded that a

comprehensive environmental performance assessment scheme for building is an

effort to achieve ‘green building’ in Hong Kong. This scheme encourages contractors


to implement effective waste management strategies, such as waste reduction, waste

reuse, and waste recycling.

The interviewees also underscored that the ISO 14001 certification has been

considered in some organisations dealing with waste management to achieve

environmental excellence; however, the environmental management system in

Vietnam is not sufficiently regulated for effective C&D waste management (R11,

R18). According to Rodríguez, Alegre, and Martínez (2007), some construction

companies in Madrid, Spain, have obtained an environmental management system

based on ISO standard 14000 to control the main environmental issues associated with

their activities, such as waste generation. By doing this, the construction companies

reap the benefits of fostering public awareness of environmental protection and

fulfilling applicable related legislation.

Therefore, it is important to strictly regulate environmental management in the

construction industry to effectively address the C&D waste issues, as one policy maker

suggested that in order to have the acceptability of urban redevelopment projects,

environmental impact assessment by the government is necessary to figure out the

environmental issues and the solutions to those issues, especially the issues of DW

(R5).

The highlight of this theme discussed by interviewees is that the environmental impact

assessment should be obligatory in construction projects through more stringent

regulations in the construction industry.

5.5.10 Cost estimation and cost-effectiveness

This theme consists of cost estimation of demolition work and waste transport and

cost-effective demolition plans. An engineer interviewee and a consultant interviewee

were in agreement that cost estimation is necessary for decision-making in DW

management, because it allows project managers to single out the best way of

conducting the projects, such as cost of demolition, cost of DW delivery and cost of

DW disposal (R4, R15). In addition, one government policy maker argued that ‘cost

analysis is also significant to achieve economic feasibility in demolition waste

management’ (R1). This resonates with a study by Yeheyis, et al. (2013), which states

that stakeholders must be well informed about the feasible cost saving of waste

reduction and the environmental impacts of C&D waste in order to avoid the

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unnecessary extra re-work in construction work. One engineering manager claimed

that ‘there are some hindrances that trigger the delayed demolition work and increase

demolition waste management cost, such as finance and the technique’ (R22). He also

suggested that ‘it is necessary to consider reducing time and cost of demolition work’

(R22).

According to Wang, et al. (2004), a successful and sustainable C&D waste

management depends on a justifiable financial framework for various stakeholders. In

addition, the study by Begum, Siwar, Pereira, and Jaafar (2006) indicated that a

benefit-cost analysis - a procedure for estimating all costs incurred and profits gained

from a business opportunity or proposal - for minimising construction waste can raise

revenue for environmental policies and prevention efforts, discourage waste disposal,

and avoid the environmental impacts of waste treatment and disposal. Therefore, it is

vital to evaluate the cost-benefit of various C&D waste management scenarios. This is

consistent with the findings by Yuan, et al. (2011).

Three interviewees (one policy maker and two consultants) claimed that the cost of

waste management is a burden for contractors, such as cost for waste classification,

waste transportation and waste disposal (R5, R13, R14). Their consensus is that cost

efficiency should be considered before projects are implemented. This is in line with

a study by Kwong (2003) showing that contractors need to build cost-effective

demolition plans. In addition, one engineer interviewee complained that ‘the evidence

of the cost saving of DW management in urban redevelopment projects can assist the

contractors in implementing DW management effectively and raise their awareness of

environmental protection’ (R7).

5.5.11 Preservation

Preservation refers to minimising the impacts of DW management on natural resources

and preserving cultural heritage. According to Yeoh and Huang (1996), there is an

increase in conservation-redevelopment conflict in urban development. This is

because rapid urban redevelopment results in the loss of cultural heritage. In line with

this perspective, the study by Chan and Lee (2008b) revealed that preservation of

historical structure and features is one of six considered urban design factors in

achieving sustainable urban renewal. This was expressed by three academic

interviewees, who articulated that urban redevelopment projects have been


implemented mainly for an economic purpose and have neglected environmental and

social needs (R8, R9, and R18). In order to approach sustainability, serious

consideration should be given to natural resource preservation and reduction of the

environmental impact on the neighbourhood. One consultant suggested that ‘the

government should have a policy on integrated sustainable demolition waste

management that covers aspects such as the preservation of surrounding areas and

the mitigation of the disturbance to community’ (R11).

It is understandable that C&D waste recovery, including reuse of C&D waste, can

reinforce the preservation of natural spaces and reduce the exploration of mineral

resources (del Río Merino, et al., 2009). However, five interviewees (two academics,

one consultant, one engineer and one policy maker) reported that in the construction

industry in Vietnam, most of the regulations rarely govern the natural resource

preservation or purely mention this issue from broad perspectives (R8, R9, R13, R15,

R20). As a consequence, there is still the problem of waste illegal dumping, which has

caused severe damage to the natural resources. One academic and one policy maker

were in agreement that there is a need for specific principles around the issues

associated with DW management, such as land-use, pollution and heritage

preservation (R9, 20).

5.5.12 Reduction of disturbance on the community

Reducing the impacts of environmental pollution and noise pollution on the

community is important in making decisions of DW management. Interviewees were

in agreement that consideration of project social performance is strictly required to

ensure a better quality of life for the community. This resonates with the study by

Farfel, et al. (2005) in that stakeholders should be more aware of demolition-related

public health problems because the process of urban redevelopment is a major source

of lead being released into the environment. Two interviewees (one academic and one

consultant) emphasised that the demolition work has acted as a source of

environmental pollution, but the contractors have not paid much attention to the

environmental safety for the community (R11, R15). This may be due to the lack of

environmental regulations in the construction industry. One policy maker

recommended that ‘it is important for the Vietnamese government to give priority to

the reduction of the impacts on the community in addition to the conventional project

objectives such as economic and environmental’ (R20).

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5.5.13 Regulations/guidelines

This theme includes the understanding the DW management procedures and providing

guidelines of DW management, which refers to promoting the best practice guidelines.

It is not easy for stakeholders to achieve efficiencies in DW management while at the

same time needing to take into account the environmental and social aspects of the

urban redevelopment projects. Therefore, it is not surprising that providing guidelines

of DW management is ranked as the most important factor for improving DW

management in urban redevelopment projects in Vietnam. The consensus among the

interviewees is that there is a lack of specific regulations or legislation for requiring

the management of C&D waste. This is in line with the situation in China, where the

lack of accurate regulations of C&D waste is one of the reasons for the poor C&D

waste management (Yuan, 2013). This means that there is no instruction to guide the

contractors in implementing C&D waste management in China. Two policy maker

interviewees conceded that there are a number of related decrees of C&D waste, but

the related regulations are too general, which is probably due to the combination

management of solid waste and C&D waste (R2, 17).

One policy maker from the government agency perceived that ‘DW management is not

normally expected to bring great profits for contractors due to its costs on the

equipment and management approaches; thus, stakeholders may be reluctant to

manage DW’ (R1). One engineer as on-site manager expressed the view that ‘in order

to fulfil the stakeholders’ responsibility in DW management, the government should

issue the guidelines for assisting all stakeholders in understanding the procedures of

DW management”’(R16). In addition, one policy maker suggested that ‘the

government should promote sustainability in urban redevelopment activities, which

will encourage stakeholders to integrate DW management in the demolition work’

(R2).

5.5.14 Stakeholder engagement

This theme explores the factors concerning the responsibility of stakeholders involved

in the DW management process and their roles in monitoring and providing feedback

about DW management. In fact, one engineer from a construction contractor reported

that ‘the stakeholders’ responsibilities of C&D waste management are regulated in

the new circular that was enacted in May 2017’ (R16). However, he also claimed that


‘these responsibilities are too general in the construction industry and there is the

need of delegation of specific responsibilities in urban redevelopment DW

management’. Two interviewees (one academic and one engineer) reckoned that urban

redevelopment DW management in Vietnam is complicated because it involves

different stakeholders, with different fields of interest (R10, R15,). One engineering

manager expressed that ‘demonstrating the key stakeholders’ role in the different

stages of the demolition process can help achieve the effective DW management’

(R22). He gave the example that ‘the collection and disposal of DW by waste

contractors is more professional and effective than construction contractors’. This is

in line with findings by Manowong (2012) in that it is significant to identify who needs

to be involved in the construction waste management process.

According to a study by Yuan (2013), the responsibilities between the government

agencies and the local authority in C&D waste management are fuzzy, which hinders

the better C&D waste management practice. One planner interviewee from the local

authority emphasised that ‘in order to fulfil the stakeholders’ responsibility in DW

management, the government should issue the guidelines for supporting all

stakeholders involved in site management and site planning for waste management’

(R12). In addition, other engineer interviewee as project manager emphasised that

‘government should take the leading role in improving urban redevelopment DW

management, which encourages and enforces the stakeholders to effectively

participate in DW management’ (R7). This resonates with the finding by Lu and Yuan

(2010), in that without a strong direction and supervision from the government in

construction projects, other stakeholders, such as clients and contractors, may be

reluctant to conduct C&D waste management.

5.5.15 Information and communication

The component involved in this theme is regular information update. The information

update is an essential means of communication among stakeholders in effective urban

redevelopment DW management. However, such data are usually recorded with

construction waste in solid waste management reports in general by the Ministry of

Natural Resource and Environment (MONRE). The consensus among interviewees is

that Vietnam currently has no inventory or exact data on DW management, such as the

141

amount of waste, waste types or recycling material rate. One academic interviewee

manifested that ‘the DW information is difficult to update and control because of the

illegal disposal of C&D waste and a poor DW management plan’ (R18). He also

suggested that ‘it is imperative to formulate the policies to prompt the contractors to

share and report the waste management information’. In addition, two-out-of-six

policy makers claimed that there is the need of establishing a database platform for

C&D waste management (R4, R19). By doing this, the key stakeholders can be active

in making DW management plans and 3R strategies. This accords with the finding by

Shen, et al. (2007), which stated that providing a tool to facilitate stakeholders in

accessing the project information and sharing the knowledge and information in

working together towards better project performance is of utter importance.

In addition, one government planner interviewee claimed that ‘sharing the information

related to DW management should be required in the early stage of demolition work

to avoid the increase in the cost of waste management due to miscommunication’ (R6).

5.6 IMPROVING DEMOLITION WASTE MANAGEMENT IN VIETNAMESE URBAN REDEVELOPMENT PROJECTS

The purpose of the interviews was to validate the conceptual framework involved in

24 critical factors of DW management in urban redevelopment projects and proposed

action plans to improve DW management in Vietnamese urban redevelopment

projects. The main findings were extracted from the interview as shown in Table 5-4.

Table 5-4: Major findings of the interview study

No. Theme Action plan

1 Demolition methods Choosing the demolition methods with the

government’s support and consultation

2 Demolition waste management procedures

Demolition procedures need to be defined clearly Effective scheduling demolition work in early stage

3 Waste classification and estimation

Promoting on-site waste classification Improving skills of waste sorting Promoting the use of recycling materials

4 Planning for landfill, sorting area, and storage

Priority of landfills and transfer stations planning Identifying suitable sites for transfer stations and

landfills


No. Theme Action plan

5 Training

Providing training courses of DW management and demolition technology

Building capacity in using low waste technology

6 Stakeholder awareness

Raising awareness of key stakeholders Promoting incentive policies

7 The uniqueness of demolition waste

Assessment of DW characteristics in the early stage of demolition work

Understanding the DW characteristics

8 “3R” strategies and recovery

Promoting specific 3R strategies Increasing reuse and recycling by intensive

economic programs

9 Environmental Impact Assessment

Regulating strict environmental policies

10 Cost estimation and cost- effectiveness

Development of cost-effective scenarios Cost estimation for specific stage of DW

management

11 Preservation Integrated preservation in DW management

12 Reduction of community disturbance

Priority given to the community’s safety in project objectives.

13 Regulations/guidelines Providing appropriate guidelines Regulations of integrated waste management Promoting sustainability

14 Stakeholder engagement

Defining clearly stakeholders’ responsibilities Enhancing efficient communication Appropriate institutional arrangement The leading role of government

15 Information and communication

Regular reporting Building database of demolition waste Sharing information in the early stage of demolition

work

The interviewees were asked to provide their comments on how influential each

critical decision-making factor is. Most of the interviewees expressed that the proposed

framework fully covered the major and relevant factors. These factors were confirmed

by the interviewees as accurate and reasonable and deserved to be considered in

improving DW management in Vietnamese urban redevelopment projects.

Regarding the three critical factors that were found, the significant differences of

respondent’s’ perspectives in rating the importance, and the consensus among the

interviewees, was made. Training is considered as important to DW management,

which can minimise waste generation and help in waste classification. In addition,

143

training in the early stage, especially on-site skill training, can remedy the impacts on

the environment and the community. In support of this factor, many studies revealed

that the C&D waste generation is substantially affected by skilled construction workers

(Lu & Yuan, 2010; Tam & Tam, 2008; Wang & Yuan, 2008). It is noteworthy that

training of DW management and demolition techniques is grouped in the theme of

‘training’.

The interviewees were in agreement that cost estimation is necessary for decision-

making in DW management, because it allows project managers to single out the best

way of conducting the projects, such as cost of demolition, cost of DW delivery and

cost of DW disposal. This is in line with a study by Kwong (2003), showing that

contractors need to build cost-effective demolition plans. As per interviewees’

suggestion, there is the need of investigation into the DW characteristics in the early

stage to assist decision makers in effective DW management. This is supported by the

research of Kofoworola and Gheewala (2009), in that the inventory of C&D waste

generation should be implemented, which provides useful information for recycling

waste strategy.

Summarily, the interview study elicited interviewees’ opinions and insights, which

assist to formulate the efficient decision-making framework or urban redevelopment

DW management. This framework will assist the decision makers in making the right

decisions in achieving effective urban redevelopment DW management in Vietnam.

In addition, the findings from the interview study are analysed and remarked as

variable actions of improving the urban redevelopment DW management in Vietnam

with 15 main themes of critical factors. Interestingly, the discussion and actions

suggested by the interviewees relating to six factors (waste classification and

estimation; planning for landfill, sorting area, and storage; the uniqueness of

demolition waste; “3R” strategies and recovery; and cost estimation and cost-

effectiveness) supported the development of the database of DW in the case study.

This information enables decision makers to assess and qualify the DW database in

making the decision for improving DW management with the better understanding and

the cost-effectiveness.


5.7 SUMMARY

This chapter illustrates the results of data analysis, which were obtained through the

semi-structured interviews with 22 interviewees from the five stakeholder groups:

academics, planners, consultants, engineers, and policy makers. It describes the in-

depth understanding of experienced respondents about the significant influence of 24

critical decision-making factors on DW management in urban redevelopment projects,

which resulted from the survey study, in Chapter 4. The findings in this chapter are the

actions suggested by the interviewees, towards improving DW management in

Vietnamese urban redevelopment projects based on critical decision-making factors.

The critical factors and conceptual decision-making framework were validated and

verified by interviewees who hold the key positions in DW management in Vietnamese

urban redevelopment projects. There is prevailing awareness towards integrated DW

management among stakeholders in achieving sustainability. This is to ensure that the

critical decision-making factors are significantly considered in improving DW

management in Vietnamese urban redevelopment projects. The findings in this chapter

answered the second research question: How do the key decision-making factors

influence demolition waste management in Vietnamese urban redevelopment projects?

This analysis was to investigate the contextual relationships among critical factors,

which will act as the foundation for developing a database supporting the decision-

making process of DW management in an urban redevelopment project. Based on the

interviewees’ feedback, six critical factors including (1) on-site sorting, (2) rate of

waste recovery, (3) cost-effectiveness demolition plan, (4) estimation of DW, (5) cost

estimation of waste transport, and (6) landfill planning, were further analysed to

develop the DW database. This database of DW is considered crucial information that

supports stakeholders in making decision. The process of database development in a

GIS-based model is described in Chapter 6.

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Chapter 6: Case study

6.1 INTRODUCTION

The conceptual decision-making framework for improving urban redevelopment DW

management in Vietnam is formulated in previous chapters. In order to develop this

conceptual framework, the critical decision-making factors were identified through the

questionnaire survey on five groups of key stakeholders in the survey study. The

conceptual framework was then discussed and validated by experienced respondents

in the semi-structured interview round in the interview study. Based on the findings

from both quantitative and qualitative analysis, as discussed in the Chapter 4 and 5,

six critical factors including on-site sorting, rate of waste recovery, cost-effectiveness

demolition plan, estimation of DW, cost estimation of waste transport, and landfill

planning were analysed to develop the database of DW in the GIS-based model. This

model is a decision support tool, which incorporates with the proposed decision-

making framework in order to facilitate decision making in DW management at district

level. The GIS-based model is designed for the case study in Hanoi, including four

mega urban redevelopment projects.

The outline of this chapter is as follows. It first describes the purpose of the case study.

This is followed by the selection of the case study conducted in this research and data

collection and analyses. The development of the decision support system based on GIS

is then presented before the case study results are discussed. The chapter ends with a

summary about the important results of the case study.

6.2 CASE STUDY PURPOSE

The case study was used as an example of the application to practically demonstrate

how the supporting database developed can assist decision makers in improving DW

management in urban redevelopment projects. In this research, ArcGIS software was

adopted as a decision support tool for developing the spatial database and Excel

software was used for data calculation. Both spatial and attribute data were collected

regarding the critical factors considered in the proposed decision-making framework.

The collected data was then computed and combined for the preparation of input data.

146 Chapter 6: Case study

Finally, the necessary information for DW management was captured for the GIS-

based model database.

This database was integrated with the proposed framework to assist decision makers

in the decision-making process. This supporting database includes the information of

DW volume, DW compositions, DW transport, and the selection of landfill sites all of

which were computerised based on six critical decision-making factors. The GIS-

based model is designed for the case study in Vietnam aiming at improving DW

management in urban redevelopment projects. The case study provided a clear

example of developing the database of DW management at district level.

6.3 CASE STUDY SITE CONTEXT

The case study was adopted as a research method and was briefly described in Chapter

3. The case study was conducted after the data of the questionnaire survey and

interviews were analysed. According to Berg (2004), the case selection should ensure

that the case provides relevant data that reflects the research hypotheses or the research

problem. There are two options of conducting case studies that the researcher can

select to collect and analyse the research data, namely single case, and multiple cases.

A single case study normally emphasises the critical, unique or unprecedented nature

of the selected case to confirm or challenge a theory; in order to avoid

misrepresentation, the researcher needs to justify carefully the selection of the case

(Blaxter, 2010; Mark, et al., 2009). On the other hand, (Blaxter (2010)) and Mark, et

al. (2009) argue that a multiple case study reflects the logical and replicable

generalisation of the research findings through different cases. These researchers also

stated that a single case study is often preferred, because the research results are

supposedly strengthened by replicating the pattern and improving the confidence in

the robustness of the theory.

In this research, a single case was employed in order to answer the research question

about the requirement of the supporting database of DW management in urban

redevelopment projects in Vietnam. The selection of case study established the

following criteria:

- The case study should be located and represented for the trend of urban

redevelopment in Vietnam.

147

- The main purpose of the case study is redeveloping the aging buildings.

- The case study should be multiple urban redevelopment projects within a

district.

- The case study will be conducted in the next 10 years and has the potential of

environmental impacts caused by DW.

Based on the above criteria, Ba Dinh, one of four old central districts in Hanoi, was

selected to develop decision support tool, GIS-based model, as illustrated in Figure 6-

1. Ba Dinh district is the political centre of Vietnam, where most of the government

offices and embassies are located. This district covers an area of about 9.25 m2,

spanning over 21°2'9.118" N and 105°49'34.928" E, with a population of 228,352 and

population density of about 24,703 people per square kilometre. It is witnessed that Ba

Dinh occupies many two-storey to five-storey building blocks built in the 1970s, most

of which have almost reached the end of their life span. In addition, many of old

buildings in Ba Dinh are severely blighted and pose serious environmental risks to the

residents’ safety (Huy, 2015). According to Vietnamnet (2016), 25 out of 42 high-risk

old buildings in Hanoi are located in Ba Dinh district, where three old buildings are at

risk level D, which is the highest risk level and can be a danger to the residents, and

22 old buildings are at risk level C. These require urban redevelopment of residential

areas, which will have the capacity to modernise neighbourhoods and improve housing

conditions on a large scale in Ba Dinh district (Hoang, 2017).

Consequently, a large volume of DW will be generated, which requires an effective

DW management. Therefore, the case study area is appropriate due to the level of

urban redevelopment and the need of DW management, which can reflect the merit of

a supporting database integrated with the decision-making framework.

At present, 7 out of 107 proposed redevelopment projects in Hanoi are completed and

8 projects, including resident and non-resident buildings, which have been approved,

have been undertaken in Ba Dinh, Thanh Xuan, Dong Da and Cau Giay districts (Bao

Anh, 2011). Ba Dinh district has four redevelopment projects that are waiting for the

commitment, which are Giang Vo; Ngoc Khanh I; Ngoc Khanh II; and Thanh Cong

(Mai Hoa, 2015).


Figure 6-1: Location of Ba Dinh district

These projects indicate that the local government is acting for the cause of urban

redevelopment, which can lead to massive DW. On the other hand, there is a lack of

plans in effective DW management in Vietnam, particularly in Hanoi. The information

of four projects in this case study is shown in Table 6-1.

149

Table 6-1: The project information of the case study

No Name of urban

redevelopment project Number of buildings

Type of building structure

Year of construction

1 Giang Vo 5 Brick-concrete

structure 1974

2 Ngoc Khanh I 3 Brick-concrete

structure 1976

3 Ngoc Khanh II 4 Brick-concrete

structure 1976

4 Thanh Cong 25 Brick-concrete

structure 1971

To specify, the Thanh Cong project is the largest project, with 25 five-floor buildings,

Ngoc Khanh I project comprises three five-floor buildings, Ngoc Khanh II project

comprises only four three-floor buildings, and Giang Vo project comprises five five-

storey buildings. All of the old buildings in those four urban redevelopment projects

are three to five-storey blocks and are dated back over 40 years. These buildings were

of brick-concrete structure, which was deemed as the major structure type in the 1970s.

This study focused on sorting and estimating the materials of brick, concrete, mortar,

and metal, wherein mortar was combined with concrete in waste estimation because

these two materials are usually attached together in the demolition process and it is

hard to classify them on-site.

6.4 CASE STUDY DATA COLLECTION METHOD

Based on the results from the survey and interviews, there are six critical factors that

can provide valuable references for decision makers in the decision-making process of

DW management in urban redevelopment projects. The critical factors are considered

to be analysed to answer the question regarding which information is crucial to develop

a supporting database of DW management, including six factors: (1) on-site sorting,

(2) rate of waste recovery, (3) cost-effectiveness demolition plan, (4) waste estimation,

(5) cost estimation of waste transport, and (6) landfill planning. The results of the case

study help to fulfil the factor of ‘regular information update’, which was ranked as the

third most important factor in the rankings.


In order to support DW management decision-making process in urban redevelopment

projects, essential information was collected to develop a supporting database. There

are two sources from which the data is collected, which are stated as follows.

6.4.1 The spatial data

The spatial information was gathered to provide background information about the

research area, locations of urban redevelopment projects, and landfill sites. Spatial data

at the district level were collected from available open-street map framework of the

research area, Hanoi land-use maps, Google satellite images, transport networks,

locations of urban redevelopment projects, and locations of C&D waste landfill sites.

Data at the project level included the locations of four urban redevelopment projects

and the buildings in each project that were digitised on Google satellite image with

fieldwork ground control checking. In addition, the locations of C&D waste landfills

were also drawn in a similar way. Figure 6-2 presents the locations of four urban

redevelopment projects in Ba Dinh district.

151


Figure 6-2: Locations of four urban redevelopment projects in Ba Dinh district

153

6.4.2 The attribute information

Attribute information, known as non-spatial data, was gathered through documents

and the site investigation, in order to provide the data integrated with the spatial

elements. The attribute data collected in accordance with the six critical factors as

mentioned above include the number of buildings in each urban redevelopment

project, the buildings’ structural types, buildings’ components, buildings’ structure

information, the capacity of landfills for C&D waste. To collect the related data, the

site visit was conducted in May 2017. The site visit evaluation was to obtain in-depth

information concerning the number of floors of the building in each project, the

number of units, the size of the units, the number and size of stairs, and the size of

corridors and the detailed information of demolition buildings in the four urban

redevelopment projects, as provided in Appendix D1. It must be accentuated that the

number of units and the number of floors could vary from building to building. In

addition, some general information may not be sufficient during the site visit process.

For example, many of the traditional iron doors and windows were also candidates for

alteration; many of them have been replaced with wooden ones by the residents.

Therefore, the component of wood was hard to estimate. In the next step, this

information was then analysed to develop the database, which is integrated with the

spatial information to constitute a supporting database for DW management.

6.5 DEVELOPMENT OF DEMOLITION WASTE DATABASE

The process of developing the supporting database for DW management includes three

steps as follows. First, the collected attribute data were calculated through Excel

software. Second, the spatial data were processed through ArcGIS software to

integrate with and link to the attribute data. Finally, the adapted data were presented

in the database in the form of map layers. The database was stored in the form of a

Geodatabase file in both vector and raster format. The GIS-based tool was used as the

platform for managing and displaying the supporting database in accordance with

selected factors.


In order to provide crucial information for decision-making, the volume of the total

DW and three main material types namely: brick, concrete and mortar, and metal of

DW were estimated. This phase demonstrates the important step for preparing the

attribution database. Through this phase, the waste conditions such as reuse, recycle,

or disposal are determined.

In the subsequent step, the spatial data were processed in ArcGIS to present specific

values related to each critical factor. In this step, the ArcGIS tool was adopted to

integrate the input data for the model. The total volume of DW, the volume of three

main DW materials, the number of pick-up trucks, and the selection of landfill sites

were assigned to the themes in ArcGIS tools. Then, it can easily access the information

pertaining to the DW of each project. For example, the information of recycling waste

per building or per project such as metal can be extracted from the database by

selecting the location of the building or project in ArcMap.

6.6 CASE STUDY RESULTS AND DISCUSSION

6.6.1 Demolition waste estimation

According to Lu (2014), estimation of the amount of C&D waste has been long

underscored for policy makers, academics, practitioners, and the like. The information

of C&D waste generation could help in designing strategies of reduction, reuse, and

recovery in order to conserve natural resources and energy by using materials more

efficiently (USEPA, 2009). This study adopted the methodology of waste estimation

as waste weight per area, which was first reported in the study by Yost and Halstead

(1996). The waste generation rate of brick, mortar, concrete, and metal in estimating

the waste volume was based on material index introduced by the Vietnam Ministry of

Construction, which is weight (kg) of material per m2.

The project DW generation was estimated in two steps. First, the measurements of

three main materials in the building of each project were conducted, and can be seen

in Appendix D1.

The volume of brick generated in each project was calculated by using Equation 1.

155

DWbp = BRf * WIb * Fn * Bn (1)

where DWbp is the volume of brick generated in each project (tons); BRf is the number

of bricks generated in each floor based on the total areas in the units and shared public

areas; WIb is waste index for brick; Fn is the number of floors in each building; and Bn

is the number of buildings in each project.

The volume of mortar and concrete generated in each project was calculated by using

Equation 2.

DWmcp = CMa * WImc * Fn * Bn (2)

where DWmcp is the volume of concrete and mortar generated in each project (tons);

CMa is the total surface areas of the units and shared public area in each floor; WImc is

waste index for mortar and concrete; Fn is the number of floors in each building; and

Bn is the number of buildings in each project.

The volume of metal generated in each project was calculated by using Equation 3.

DWmp = Mu * WIm * Fn * Bn (3)

where DWmp is the volume of metal generated in each project (tons); Mu is the volume

of metal generated in each floor of the building based on the metal estimation in each

unit; WIm is waste index for metal; Fn is the number of floors in each old building; and

Bn is the number of buildings in each project.

Accordingly, in the next step, the total volume of DW generation in a project was

calculated by using Equation 4. The results show that 162,860 tons of DW is a

significant waste stream, which must be analysed in making plans of waste

management by reusing on-site and off-site, recycling, or disposal. The waste

estimation of the total DW per building and per project was created in Excel software

as attribute information. Then, all the attribute data were integrated in layout ArcGIS

tools. The total volume of DW corresponding with the four urban redevelopment

projects can be seen in Figure 6-3.


DWp = DWbp + DWmcp + DWmp (4)

where DWp is the total volume of DW generated in each project (tons); DWbp is the

volume of brick generated in each project; DWmcp is the volume of concrete and mortar

generated in each project; DWmp is the volume of metal generated in each project.

The estimation result of DW generated in the four projects is summarised in Figure 6-

3 and presented in the GIS model in Figure 6-4. As is illustrated, Thanh Cong is the

largest project with a total DW volume of about 124,788 tons and Ngoc Khanh II is

the smallest project, predicted to generate 5,405 tons of DW.

Figure 6-3: The total volume of DW generation in four urban redevelopment projects

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

Giang Vo Ngoc Khanh I Ngoc Khanh II Thanh Cong

DW volume

157

Figure 6-4: The DW volume generation in four projects presented in GIS model


6.6.2 Demolition waste classification

The statistics of DW components is useful information for decision makers in

formulating DW recycling and reuse strategies and analysing cost-effectiveness. The

data listed in Appendix D1 demonstrates that the statistics of three main materials for

the four urban redevelopment projects were determined by the equations mentioned

above. By integrating the estimation results in ArcGIS tools, the performance of

different materials per building and per project is presented. Figure 6-5 shows the main

material components of DW in four projects.

Figure 6-5: Demolition waste generation divided by materials in four urban redevelopment projects

The proportion of bricks in four projects was comparatively higher, ranging from

45.3% to 47.5%, whereas the second major material of DW in urban redevelopment

projects is a combination of mortar and concrete, ranging from 43.8% to 44.7%. These

components should be considered for on-site reuse or transported to the transfer station

for reuse in other constructions such as road base and public fill areas. Metal is

considered as recyclable material accounting a negligible proportion, ranging from

0.3% to 0.7%. These data were integrated in the GIS model as shown in Figure 6-6.

0.0

20,000.0

40,000.0

60,000.0

80,000.0

100,000.0

120,000.0

140,000.0

Giang Vo NgocKhanh I

NgocKhanh II

ThanhCong

Other

Metal

Mortar and concrete

Brick

159

Figure 6-6: Demolition waste generation divided by materials in four urban redevelopment projects presented in GIS model


It is noteworthy that each sorting material could be extracted in a new layer that can

help decision makers in further analysis and statistics. This can help contractors in

urban redevelopment projects to identify the DW information in a particular building

or project, regarding the waste component volume, reuse, and recyclable materials.

In addition, separate analysis of different materials in different layers can help decision

makers in drawing up plans of demolition and estimating cost-effectiveness for DW

management. For example, the information of mortar and concrete can help

contractors decide on which scale reuse should be done and estimate the cost of waste

transport. Furthermore, by this approach, contractors can save time in making

decisions about reuse and recycling. The estimation of the number of trucks that are

used to deliver each type of DW is described in the next section.

6.6.3 Demolition waste transport

According to Cheng and Ma (2013), estimation of the number of trucks for waste pick-

up is needed for two reasons. First, if the number of trucks is underestimated, the waste

pick-up truck could be overloading because the contractors attempt to load all the

waste, which can lead to a fine imposed by the local authority. On the other hand,

overestimating the number of trucks will cost contractors money as well as result in a

waste of space for waste loading. Therefore, it is vital to provide the estimation of the

number of trucks for picking-up different types of DW. Accordingly, decision makers

and contractors could plan an effective DW management. The number of trucks per

project is estimated for picking-up bricks, mortar and concrete, which are considered

as non-inert materials by Equation 4.

TRn= DWinp/DWtr (4)

where TRn is the number of pick-up trucks in each project; DWinp is the total volume

of inert materials in each project (tons) which are based on the total volume of bricks,

mortar and concrete; DWtr is the truck capacity (tons).

In this study, the number of trucks for waste transport per project was estimated with

a truck’s capacity of 24 tons as shown in Figure 6-7. Accordingly, the Thanh Cong

project requires the largest number of pick-up trucks, amounting to about 4,755 trucks.

161

Figure 6-7: Estimation of the number of pick-up trucks per project for non-inert waste


The number of pick-up trucks for Ngoc Khanh II project is much lower, at about 203

trucks. Estimation of the number of pick-up trucks for DW in each project is vital for

contractors to formulate strategies in order to save time and the cost of DW

management.

Supposing the project has a plan of reusing non-inert waste on-site, the number of

pick-up trucks is estimated based on the volume of DW that need to be transported

after the total DW generated and the volume of DW to be reused in the project are

estimated. The reuse of DW on-site is effective DW management in reducing waste

transport cost and the amount of waste to the landfill. In addition, decision makers can

select appropriate transfer stations and C&D waste landfills based on transportation

routes in order to save time and energy for waste transport.

6.6.4 Selection of landfill sites

According to Kontos, Komilis, and Halvadakis (2005), properly selected landfill sites

for multiple solid waste could reduce the cost of waste disposal and minimise the

environmental impacts. Recently, GIS has been considered a powerful tool in waste

management, particularly in selecting the landfill sites (Kontos, et al., 2005; Şener,

Şener, Nas, & Karagüzel, 2010). In fact, in Vietnam, the cost of DW transport is one

of the major obstacles that make contractors reluctant to implement DW management.

Therefore, it is of great importance to minimise the distance from DW location to the

landfills or transfer stations.

This research created a database for selecting landfill sites, regarding the provided

number of C&D waste landfill sites in Hanoi, the landfill site capacity (ton per day),

and the distances to the landfill sites, as shown in Figure 6-8. According to the Hanoi

Department of Construction, 13 landfill sites were designed for C&D waste disposal

with different capacities, ranging from 150 to 4,000 ton per day (Nguyen, 2011) (refer

to Appendix D2). Three out of twelve landfills have no data of the site’s capacity. The

distances from waste locations to the landfills were calculated by Google Earth to

identify the optimal routes. The shortest distance from the waste location is 8.4km,

which is the location of the Lam Du landfill site, with no data of the site capacity.

163

Figure 6-8: The information of C&D waste landfill sites in Hanoi


Similarly, the distance from the waste location to Ngoc Thuy landfill site is only

8.6km, but the site capacity has not been taken into consideration. These could hinder

the contractors to make decisions of waste disposal to these two landfills. On the

contrary, Xuan Son landfill site has the longest distance to the waste location (50.3km),

with the largest site capacity (4,000 ton/per day).

At the district level, the total volume of DW was about 124,778 ton as can be seen in

Figure 6-3. Thus, the scenarios of DW disposal are vitally considered because the large

volume of DW stream. It is noteworthy that the information of the landfill site only

provides supporting data for the decision makers in choosing the landfill site or transfer

station so that the cost of DW transport can be lowered.

6.7 SUMMARY

The supporting database developed in the GIS-based tool is useful information for

decision makers to make DW management decisions in urban redevelopment projects.

The layer maps present the quantitative and objective references for the decision-

making process as a decision support system. The selected factors conceptualised to

develop the database include six factors: (1) on-site sorting, (2) rate of waste recovery,

(3) cost-effectiveness demolition plan, (4) waste estimation, (5) cost estimation of

waste transport, and (6) landfill planning. Thanks to the supporting database integrated

in GIS-based model and convenient access to this database, stakeholders can

effectively and efficiently communicate with others involved in the decision-making

process of DW management and create a platform of DW information before and

during demolition work. The findings in this chapter answered the third research

question: What is the necessary information to support key stakeholders in demolition

waste management in Vietnamese urban redevelopment projects at the district level?

This chapter presents the development of a supporting database in the GIS-based tool

under the context of four urban redevelopment projects in Ba Dinh district, Hanoi,

Vietnam. The development of the supporting database involved waste estimation,

waste classification, waste transport and selection of landfill sites. This GIS-based

model (including the DW database) was integrated with the proposed decision-making

framework. The research findings are summarised and discussed in the next chapter.

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Chapter 7: Discussion and Findings

7.1 INTRODUCTION

This chapter explains and discusses the results of the research. The findings from

Chapters 4, 5 and 6, as well as relevant literature of DW management in urban

redevelopment projects are incorporated in order to achieve the third research objective

which is ‘developing a decision-making framework and critical supporting information

to assist decision makers in improving demolition waste management in Vietnamese

urban redevelopment projects at the district level’. Accordingly, the conceptual

framework as presented in Chapter 2 is explained. The findings from Chapter 4 and 5 that

validate the conceptual framework are discussed in detail. Next, the discussion about the

development of the supporting database by the GIS model as presented in Chapter 6 is

discussed before the research findings are provided and linked to the extant literature.

7.2 CONCEPTUAL FRAMEWORK

The research commenced with a literature review focusing on urban redevelopment, the

link between sustainability and urban redevelopment, DW management, the context of

DW management in Vietnamese urban redevelopment, and organisational decision-

making. This literature review was conducted to address the first research objective,

which is ‘explore the current DW management in urban redevelopment projects and in

the context of Vietnam’.

This provided the useful knowledge to investigate domains of information that are needed

to formulate the research gaps and the factors affecting DW management decision-

making in urban redevelopment projects, which served as the foundation to formulate the

conceptual framework. To be specific, research gaps indicated that there are many

challenges in managing urban redevelopment DW due to the complexities involved, such

as poor waste management planning, the overlapping of responsibility and ineffective

time and cost management (Lu, Lau, & Poon, 2009; Wu, Yu, Shen, & Liu, 2014).

Therefore, effective waste management requires a clear decision-making process that

includes key stakeholders and involves project performances towards sustainability.

166 Chapter 7: Discussion and Findings

The knowledge of sustainable urban redevelopment, integrated waste management, and

organisational decision-making are embedded in the conceptual framework, in which 19

themes for analysis are identified and categorised into five categories including technical,

environmental, economic, social, and institutional. Analysing the multi-criterion themes

can help decision makers understand the influencing factors of DW management in urban

redevelopment projects. For example, considering the preservation of natural resources

and heritage ensures the social sustainability of DW management. In addition, urban

regeneration projects can be a source of conflict if they are poorly planned (Yau & Ling

Chan, 2008). In light of this, the engagement of key stakeholders in implementing DW

management also needs to be carefully planned in order to avoid the overlap of

responsibilities. This is supportive in saving time and cost in urban redevelopment

projects. Furthermore, demolition techniques should also be considered before the

demolition work to facilitate the urban redevelopment DW management process. Thus,

choosing an appropriate demolition method can ease on-site waste sorting and increase

the waste recovery rate (Poon, et al., 2004). Furthermore, considering the environmental

factors, such as understanding associated environmental issues, applying 3R strategies,

and raising environmental awareness, can assist in addressing the environmental impacts

of urban redevelopment projects.

Based on the background literature, a number of issues covering five main categories

including technical, environmental, economic, social, and institutional, have been

analysed and grouped into 19 main themes. As a result, a list of 53 factors that potentially

influence DW management decision-making was synthesised. For example, six decision-

making factors including DW management procedure, waste sorting, waste estimation,

planning for landfills, planning for sorting area, and planning for area of recycling waste,

were investigated regarding the theme of ‘DW management process’. The theme of

‘policy and guideline’ was composed by two factors which are ‘providing guidelines of

DW management plan’ and ‘accomplishing government’s policy and strategy on DW

management’.

The conceptual framework in improving DW management in urban redevelopment

projects was developed covering 5 categories with 19 main themes, whereas 53 decision-

making factors were used as a baseline to design questionnaires in the survey study. These

findings revealed the concern about urban redevelopment DW management in both

academic and practice as well as the factors influencing the decision-making process.

167

Related literature highlights that developed countries, such as in the United Kingdom,

other Europeans countries, and the United States, have better understanding of urban

redevelopment DW management. For example, the rate of recovery C&D waste in

Denmark, Belgium, and Netherlands, are relatively high (Brodersen, et al., 2002). In

addition, upon the trend of urban redevelopment which is occurring in China and Hong

Kong, many researchers are placing greater emphasis on various aspects in urban

redevelopment DW management, such as environmental performance, stakeholder

engagement, and decision support. These contributions are proposed to help other

developing nations, such as India and Brazil, where they seem to be comparatively less

active in researching the demolition waste management. Therefore, in order to improve

decision-making process of DW management in the context of Vietnamese urban

redevelopment projects, the original conceptual framework (as shown in Figure 2-11) was

further refined and revised based on the survey and interview findings.

7.3 REVISED CONCEPTUAL FRAMEWORK

Apart from revising the conceptual framework by analysing stakeholders’ perspectives in

the survey study, the interview study verified the proposed framework by asking for

expert opinions. In this research, the survey was conducted to answer the first research

question: What are the key decision-making factors influencing demolition waste

management in Vietnamese urban redevelopment projects? The interview study was

implemented to answer the second research question: How do the key decision-making

factors influence demolition waste management in Vietnamese urban redevelopment

projects?

In this regard, the second research objective was addressed, which is ‘identifying critical

decision-making factors of DW management in urban redevelopment projects’. Central

to this objective were three other related sub-objectives: investigating the different

concerns and expectations of key stakeholders in making decisions about urban

redevelopment DW management; identifying the critical decision-making factors in

achieving effective DW management; and developing the action plans for each critical

factor to enhance DW management.

In the survey study, the quantitative analysis generated 24 out of 53 decision-making

factors which were found to have influence on DW management in Vietnamese urban

redevelopment project. The framework was revised based on 24 critical factors as


presented in Figure 4-2. Most of these critical factors gained consensus across the five

stakeholder groups, while there were some differences in the rating regarding levels of

importance. The deep understanding of those critical factors was explored in the interview

study, which also revealed the actions in improving urban redevelopment DW

management in Vietnam. These factors have been assessed against five categories,

namely, technical performance, environmental performance, economic performance,

social performance, and institutional performance representing aspects of sustainability,

as discussed below.

7.3.1 Technical factors

Eight critical factors were found relating to the technical aspect of sustainability practice.

These factors comprised ‘determining the procedure’, ‘on-site sorting’, ‘the amount of

DW management’, ‘landfill planning’, ‘choosing of demolition methods’, ‘training of

DW management and demolition technique’, ‘sorting platform planning’, and ‘planning

storage for recycled materials’, which were categorised under five themes.

Choosing demolition methods

Choosing demolition technology is very important to DW management because the right

technology leads to reduction of DW generation and improvement of the waste

classification. This is consistent with the finding by Yeheyis, et al. (2013) in that the rate

of reuse and recycling of C&D waste mainly depends on the demolition method employed

to remove materials from a structure. In this light, interview results expressed that it is

important to determine the demolition methods in achieving the cost-effectiveness in DW

management.

Demolition waste management procedures

Determining the procedures of DW management processes was identified as an important

factor influencing the DW management decision-making. This is in line with the finding

by Poon, et al. (2001), which adds that effective waste management on the construction

site usually involves scheduling from waste clearance, waste collection and waste

disposal, which should be developed before construction activities. The interview results

also reflected that scheduling would help contractors manage time effectively, minimise

problems during demolition work and increase the rate of waste recovery. Thus, a detailed

and comprehensive plan of C&D waste management in conducting the construction

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project is needed to achieve the waste minimisation and high level of recycling waste

(Yeheyis, et al., 2013; Yuan, 2013).

Waste classification and estimation

This theme includes the decision-making factors of on-site sorting and waste estimation,

which has garnered scrupulous attention from the respondents in the questionnaire survey.

Wu and Ann (2014) highlight that on-site sorting that is effectively implemented would

assist the contractors in arranging materials and using them properly. In addition, via this

strategy, the contractors can increase the value of recyclable waste and avoid the pollution

of mixed materials. Interestingly, ‘on-site sorting’ was ranked the third in terms of its

importance by key stakeholders. The result of the interview study also revealed that the

main issues of C&D management in Vietnam include the lack of on-site sorting practice

and the fact that most of C&D waste generated in construction projects was mixed and

even disposed together with municipal solid waste. Thus, it is important to integrate on-

site sorting in DW management plans.

Waste estimations are more supportive of the management process for they enable

operational cost and information of waste generation, which is useful for managers in

controlling projects (Formoso, et al., 2002). It was also discussed in interview results that

DW estimation should be scheduled in the early stage as this information can help

decision makers improve cost and time effectiveness. It is noteworthy that estimation of

DW generation and its components in many urban redevelopment projects is to assess the

feasibility of recycled materials on a large scale.

In line with the importance of waste sorting and waste estimation in implementing DW

management, the DW database, such as waste amounts and compositions, was considered

in developing the supporting decision-making process. For example, the estimation of

metal materials was found to help decision makers in planning for recycling waste,

including recycling storage and waste transport. Four recent urban redevelopment

projects in Ba Dinh district, Hanoi, Vietnam were investigated via a case study in order

to develop the database to be used in urban redevelopment DW management. The amount

of DW and its compositions were calculated for a single aged building and a single

project. The development of database and associated discussion was presented in Chapter

6.


Planning for landfill, sorting area, and storage

It is understandable that the planning of DW from generation, collection, and disposal

offers more benefits to effective DW management, such as increasing the recovery rate,

reducing cost and time of waste transport and remedying the impacts of DW on the

environment. The interview results revealed that the issues of collection, transport, and

disposal of DW need to be addressed by promoting the planning of waste storages, waste

transfer stations and specific waste landfills. In this view, Yuan (2013) highlights that

planning waste recycling facilities based on the transportation distances throughout the

region can save the waste transportation cost and increase the contractors’ awareness of

sending waste to recycling facilities because of the convenience in transportation.

Thus, the saving of time and cost in the DW management process focused not only on

onsite works but also in the transportation of waste to the landfills or storage. The

information of landfills, including the landfill capacity and landfill location, was found to

be important in choosing the most cost-effective options for waste transportation. This

information was used as input data in the case study to compute the scenarios of DW

disposal in the landfills so that the cost-effectiveness considered.

Training

According to del Río Merino, et al. (2009), all construction projects impact the

environment due to the use of raw materials, environmental pollution, energy

consumption, and waste generation. In addition, choosing the appropriate demolition

method can ease on-site waste sorting and increase the waste recovery rate (Poon, et al.,

2004). Therefore, training human resources and skilled personnel involves the decision-

making process, which is a prerequisite for improving DW management in urban

redevelopment projects. However, there was a significant difference between the five key

stakeholders’ perspectives in the survey study. The 2-sample t-test revealed that engineers

and policy makers paid more concern to the need of training in DW management. The

influence of training in DW management was discussed in the interview study, which

helps stakeholders in minimising and classifying of DW. The interview results reflected

that sufficient training for the workforce involved in DW management is the most

important, raising the workforce’s awareness about DW management and the use of

advanced technology in waste classification. The interview results also unveiled that the

limited knowledge of demolition work and waste management may lead to the problems

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of DW management in urban redevelopment projects, such as the low rate of waste

recovery and increased cost of waste management.

7.3.2 Environmental factors

Five critical factors were identified related to the environmental aspect of sustainability

practice. These factors comprise ‘promotion of 3R’, ‘the willingness of stakeholders’,

‘the uniqueness of DW’, ‘rate of recovery’, and ‘environmental impact assessment’,

which were categorised into four themes.


Stakeholder awareness refers to the willingness of stakeholders to undertake DW

management. Lack of interest and understanding among stakeholders could hinder the

improvement of DW management in urban redevelopment projects. Interview results

reflected that the efficiency of DW management depends on the awareness of

stakeholders on the classification of DW, waste recycling and waste disposal. Equally

importantly, practitioners’ perspectives on resource saving, environmental protection is a

vital factor of C&D waste minimisation, through changing attitudes towards waste

generation, classification, recycling, and disposal (Manowong, 2012; Osmani, et al.,

2008).

The uniqueness of demolition waste

One of the concerns voiced by stakeholders in the decision-making process is to

understand the nature of DW in order to implement effective DW management. However,

interview results reflected that the characteristics of DW presented a low potential of

recycling compared to waste from new construction. Poon (1997) also highlights that

masonry, wood, concrete and brick typically produced more than half of DW

management. The different economic contexts would lead to the difference in the

selection of construction materials. In addition, the survey results showed that engineers

paid less attention on this factor than other groups including academics, planners, and

consultants. This suggests that insufficient knowledge of DW may lead to a poor DW

management plan for waste recycling, waste reuse, and waste disposal. Thus, there is a

need for investigating the DW characteristics in the early stage to assist the decision

makers for effective DW management.


‘3R’ strategies and recovery

The survey results show that ‘3R’ principles and waste recovery are the key decision-

making factors of DW management in urban redevelopment projects. These strategies

should be given high priority when selecting waste disposal measures (Peng, et al., 1997)

since that could increase waste recovery rate and remedy environmental impacts, as well

as pressure on landfills. This finding resonates with the study by Yeheyis, et al. (2013) in

which reusing and recycling of C&D waste are considered the challenges to the

management of large amounts of waste, in achieving sustainable construction. However,

in Vietnam, 3R strategy is often neglected by contractors for many reasons, such as the

lack of stakeholders’ awareness, poor waste management plans and the lack of low waste

technology applications. Therefore, promoting 3R in C&D waste management yields to

a higher waste recovery rate.

In order to effectively implement 3R strategies, the DW compositions need to be clearly

assessed. The estimations of different kinds of DW, such as bricks, metal, and mortar, are

supportive of reuse and recycling plans so as to increase the rate of waste recovery. For

example, based on the amount of mortar, contractors can compute for the rate of on-site

reuse or reuse for other construction elements. Therefore, the decision-making factor of

‘rate of recovery’ was selected to be computerised in the GIS-based model as presented

in Chapter 6.

Environmental impact assessment

Environmental impact assessment is a particularly important process of evaluating the

likely environmental impacts of a project that needs to be considered in urban

redevelopment DW management with regard to sustainability. The study by del Río

Merino, et al. (2009) highlights that all construction projects impact the environment

through the use of raw materials, environmental pollution, energy consumption, and

waste generation. Therefore, environmental impacts assessment is required to examine

the anticipated environmental effects of urban redevelopment DW management projects.

Although this approach is regulated in Vietnam’s law on environment protection, it is still

not effectively implemented.

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7.3.3 Economic factors

Cost estimation and cost-effectiveness

Three critical factors were investigated related to the economic aspect of sustainability

practice. These factors included ‘cost-effectiveness’, ‘cost of demolition’, and ‘cost of

waste transport’, which were categorised into the theme of ‘cost estimation and cost-

effectiveness’. Cost-effective plans would assist stakeholders in saving energy and the

DW management cost, as well as the cost of demolition work. The study by Yeheyis, et

al. (2013) highlights that contractors must thoroughly analyse about the feasible cost of

waste reduction and the environmental impacts of C&D waste in order to avoid the

unnecessary extra cost and re-work during the construction.

In the survey study, the factor of ‘cost of waste transport’ was perceived differently by

stakeholders. Engineers and policy makers consider waste transport with high importance

level, while planners and consultants did not have significant concern for this factor.

However, the results from the interview study reflected that the evidence of the cost

saving of DW management can assist the contractors in implementing DW management

effectively, which include the cost of demolition and cost of DW management delivery.

Therefore, cost efficiency should be considered before projects are implemented.

Since stakeholders in Vietnamese urban redevelopment projects were found to be

reluctant to implement DW management, it is imperative to assess the cost-effectiveness

of DW management, including waste transportation, in order to reduce the cost of

management. Therefore, the two economic factors which are cost-effectiveness and cost

of waste transport were elaborated in the GIS-based model via a case study. This involved

the analysis of the number of trucks for loading of different types of DW and the optimal

routes of waste transport to the landfills.

7.3.4 Social factors

Only two critical factors were investigated related to the social aspect of sustainability

practice. These factors comprised ‘preservation’ and ‘reduction of community

disturbance’.

Preservation


Preservation refers to minimising the impacts of DW management on natural resources

and preserving cultural heritage. Heritage should be preserved properly for the enjoyment

of society through different generations (Fung, 2004). Interview results revealed that the

government should adopt a policy on integrated sustainable DW management that covers

aspects such as preservation of surrounding areas. This is consistent with the findings by

Chan and Lee (2008b), in that the preservation of historical structures and features is one

of six considered urban design factors in achieving sustainable urban renewal. Therefore,

natural resource preservation and reduction of environmental impacts on the

neighbourhood should be seriously considered to achieve sustainability.

Reduction of disturbance on the community

Similarly, reducing the impacts of environmental pollution and noise pollution on the

community is important in making decisions about DW management. Interview results

indicated that the Vietnamese government needs to give priority to reducing the impacts

of environmental pollution and noise pollution on the community, in addition to the

conventional objectives such as economic and environmental ones. The study by Farfel,

et al. (2005) highlights that stakeholders should be more aware of demolition-related

public health problems because the process of urban redevelopment acts as a major source

of lead released into the environment. Thus, consideration of project social performance

is strictly required to ensure a better quality of life for the community.

7.3.5 Institutional factors

Five critical factors were found related to the institutional aspect of sustainability practice.

These factors comprised ‘providing guidelines’, ‘stakeholders’ responsibilities’, ‘roles of

stakeholders’, ‘regular information update’, and ‘understanding the procedure’, which

were categorised under three themes.

Regulations/guidelines

This theme includes understanding the DW management procedures and providing

guidelines of DW management, which refers to promoting the best practice guidelines.

Among all influenced factors, ‘Guidelines of DW management’ received the highest

rating from five of the key stakeholder groups. This finding echoes the notion that a good

policy system is considered the most important factor of successful waste management in

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construction projects (Lu & Yuan, 2010). In fact, interviews conducted in Vietnam

demonstrated that DW management is not normally expected to offer profits to

contractors due to the costs of equipment and management approaches; thus, stakeholders

may be reluctant to manage DW. Consequently, in order to fulfil the stakeholders’

responsibilities in DW management, the government should issue the guidelines for

assisting all stakeholders in understanding the procedures of DW management.


This theme pertains to the factors of the responsibility of stakeholders involved in the

DW management process and their roles in monitoring and providing feedback on DW

management, as was revealed from the survey study. In Vietnam, stakeholders’

responsibilities are too general and obscure in the construction industry. The fuzzy

responsibility between the government agencies and the local authorities in C&D waste

management obstructs the better C&D waste management practice (Yuan, 2013). Specific

responsibilities need to be clearly allocated in urban redevelopment DW management. In

addition, in order to fulfil the stakeholders’ responsibilities in DW management, the

government should issue the guidelines for supporting all stakeholders involved in site

management and site planning for waste management.

Information and communication

The component involved in this theme is regular information update, which is essential

communication among stakeholders in effective urban redevelopment DW management.

In Vietnam, the DW information is difficult to update and control because of the illegal

disposal of C&D waste and a poor DW management plan. It is imperative to formulate

policies to encourage the contractors to share and report the waste management

information.

The finding by Shen, et al. (2007) also highlights that it is necessary to provide a tool to

expedite stakeholders’ access to the project information and share the knowledge and

information, while collaborating for better project performance. It is noteworthy that

sharing information about DW management should be required in the early stage of

demolition work to avoid the increase in the cost of waste management as a result of

miscommunication.


In conclusion, the responses of the interviewees indicated that the critical factors

identified in the survey study are important to improve DW management in urban

redevelopment projects in Vietnam. In addition, the action plans were proposed by

interviewees in order to solve the problems associated with each factor. The interview

findings also provided the suggested actions corresponding with critical decision-making

factors, which were towards improving DW management in Vietnamese urban

redevelopment projects (Table 5-4). Based on the action plans, the DW databases were

identified to support decision makers to make decisions about DW management in urban


The crucial information of DW management includes the volume of DW and its

components, the rate of recycled materials, and the distances of waste transport. With

reference to the decision-making process, specific factors for DW management were

identified. The crucial information is in accordance with the critical factors: (1) on-site

sorting, (2) rate of waste recovery, (3) waste estimation, and (4) planning area for

landfills. This DW database also provided a cost-effective analysis, which answers the

questions related to two critical factors: (1) cost-effective demolition plans and (2) cost

estimation of waste transport. All of DW database was integrated in the GIS-based model,

which supports the requirement of regular information updates.

7.4 GIS-BASED DECISION SUPPORT SYSTEM

Based on the critical factors extracted from survey and interview study, the supporting

database of DW management decision-making was introduced in a GIS-based tool. The

critical factors are considered to be analysed to answer the question regarding the type of

information, which is crucial in developing a supporting database of DW management,

including six factors: (1) on-site sorting, (2) rate of waste recovery, (3) cost-effective

demolition plan, (4) waste estimation, (5) cost estimation of waste transport, and (6)

landfill planning. Based on these critical factors, the supporting database includes the

information of DW volume, DW types, and DW transport, and the selection of landfill

sites.

Accordingly, crucial information about DW should be given to DW management

characteristics in an urban redevelopment context. This aimed to address the third

177

research question: What is the necessary information to support key stakeholders in

demolition waste management in Vietnamese urban redevelopment projects at the district

level?

A case study of four urban redevelopment projects in Ba Dinh district was adopted to

develop the database of DW. Estimating the generation of DW helped in classifying DW

components of bricks, mortar, concrete, and metal. Through the GIS-model, a

comprehensive supporting database for decision-making was provided. In the database,

the portion of potential recycled materials such as metal is relatively low, accounting for

0.3% to 0.7%. This is due to the nature of DW in urban redevelopment projects in

Vietnam.

However, reuse and recycling of the components such as bricks, mortar, and concrete

should be considered for such purposes as reuse on-site, public fills, or road base. The

information of the amount of DW components in Ba Dinh urban redevelopment projects

can help contractors devise plans of effective reuse or recycling of waste.

In addition, the number of pick-up trucks was estimated for inert materials such as brick,

mortar, and concrete. It is hard to accurately estimate the required number of trucks for

metal materials in demolition sites due to the large volume. Furthermore, the optimal

routes of DW transport to the C&D waste landfill sites and the landfill sites’ capacity per

day were provided in a GIS-based model. This supporting information can save

contractors time and cost of DW management. For example, the fuel consumption of DW

transport can be reduced by choosing the optimal routes.

The supporting database maps generated are beneficial towards DW management

decision-making in urban redevelopment projects. These maps present a quantitative and

objective reference for the decision-making process, which helps decision makers on the

subjective and qualitative judgement. As the demolished buildings in four urban

redevelopment projects in Ba Dinh district are aged over 40 years and their structured

information is not sufficient, GIS-based model is the most suitable in DW management

at the district level. It makes great use of the information stored in spatial maps by

incorporating the GIS map displayed in spatial information, of each building in each

project at the district level.


7.5 FINALISED DECISION-MAKING FRAMEWORK

Based on the findings of the survey and interview study, the proposed framework

presented in Chapter 4 (Figure 4-2) was finalised by integrating the findings from the case

study. The finalised decision-making framework is shown in Figure 7-1. This, together

with the development of a decision support system, helps achieve the third research

objective, which is ‘developing a decision-making framework and critical supporting

information to assist decision makers in improving demolition waste management in

urban redevelopment projects at the district level’.

The finalised decision-making framework consists of the decision-making factors and

supporting database, which facilitates stakeholders to effectively assess and qualify the

demolition waste database in different urban redevelopment projects. The 24 decision-

making factors were explored by investigating the multi-criteria of DW management

issues in the background literature and analysing both quantitative and qualitative data in

the survey and interview study. Thus, the conceptual framework was validated upon the

perspectives of key stakeholders in Vietnam, which are argued to contribute to addressing

the DW management issues in Vietnamese urban redevelopment projects. Meanwhile,

special consideration of supporting database was placed on six critical factors. These

critical factors were analysed and computerised to develop database of DW in GIS-based

model with spatial and attribute information.

The integrated framework creates a collaborative platform of DW management

information. The engagement of stakeholders in assessing and qualifying the DW

database before the demolition process becomes a key factor contributing to the

effectiveness of DW management in urban redevelopment projects. The finalised

decision-making framework is beneficial to decision makers in making decision in

Vietnamese urban redevelopment DW management. Firstly, perspectives of integrated

waste management and sustainable urban redevelopment are embedded in the framework,

which reinforce the importance in raising stakeholders’ awareness. In addition, a GIS-

based model, as the decision support tool, facilitates decision makers in analysing DW

database for the purposes of cost and plan effectiveness. Thirdly, stakeholders can easily

communicate with other stakeholders participated in the decision-making process. With

the decision-making framework and the support of the GIS model, the stakeholders can

179

effectively convey their ideas about the influencing factors and crucial information to

other stakeholders. As a result, considering sustainability aspects, costing and planning

effectiveness and stakeholders’ communication can help improve the decision-making

process of urban redevelopment DW management.

Thus, a plan aiming at saving cost and time, while minimising the environmental impacts

should be taken into account in achieving effective DW management. The integration of

a GIS-based model and the decision-making framework is a typical example of

collaborative decision-making in improving urban redevelopment DW management at

the district level in Vietnam.

It is noteworthy that the ages of old buildings in Vietnamese urban redevelopment

projects are commonly over 40 years old. Thus, the compositions of DW may be different

from that in other countries. In addition, due to the specific economic and policy context

in Vietnam, the decision-making factors may be rated differently by the five stakeholder

groups from that in other developed and developing countries. However, the proposed

decision-making framework may be considered in similar developing countries, such as

China, Brazil, and India which have similar considerations in urban redevelopment

projects, stakeholder engagement, and development context.


DW

man

agem

ent i

n ur

ban

rede

velo

pmen

t pro

ject

s

Technical

Choosing demolition method

DW management procedures

DW estimation The total volume of DW generation

DW classification The volume of devided materials

Planning for landfill, sorting area and storage Landfill location and capacity

Training

Environmental


The uniqueness of DW

3R strategies and recovery The information of reused materials


Economic

Cost-effectiveness

Distances to landfill, number of pick-up trucks, landfill information, and potential recycled DWCost estimation of demolition

Cost of DW transport Distances to landfill and number of pick-up trucks

SocialPreservation

Reduction of disturbance

Institutional

Best pratice guidelines


Information & communication

Decision-making factors Supporting database

Attribute data

Spatial data

. Land-use map/satellite image of sites to be redeveloped

. Locations of projects and C&D waste landfill sites

. Map of transport networks

Quantitative support

. Building information (name, address, structure type, surface areas)

GIS tools

Figure 7-1: Finalised decision-making framework for improving DW management in urban redevelopment projects at district level

181

7.6 FINDINGS RELATED TO THE EXTANT LITERATURE

Urban redevelopment is a hot topic emerging globally, particularly in developing

countries (Zheng, et al., 2014). As a result, a big issue concerning practitioners and

academics for years is DW management decision-making with regard to sustainability

in urban redevelopment projects, as reviewed in Chapter 2. The recent research has

contributed to DW management in urban redevelopment projects regarding decision

support, environmental challenges, stakeholder engagement, strategy and solution, and

evaluation.

The key knowledge gaps in current research and recommendations for future research

were identified under four main topics: decision support, decision-making, stakeholder

engagement, and evaluation. Thus, there is potential to explore and expand knowledge

in these disciplines, particularly in view of the complexities and challenges involved

in implementing DW management in urban redevelopment projects. The knowledge,

insights, and recommendations provided help establish a framework to critically

address the issues associated with urban redevelopment DW management in order to

further promote the sustainability of urban redevelopment. The integration of the

framework with the GIS-based database is an effective support for the decision-

making process.

The results from the survey and interviews revealed critical factors that guide the

improvement of DW management in urban redevelopment projects. These factors also

formed a basic knowledge for DW management in achieving sustainable urban

redevelopment. In addition, the findings of the research indicate that effective DW

management expanding to sustainable practices should be supported by the

willingness of the stakeholders to improve their knowledge and skills. The interviews

in this study also discussed the significant factors needed to improve DW management

in urban redevelopment projects, which provided profound insights from the experts

and verified the theoretical assumptions and survey results.

The essence of this research is to find more knowledge and add to the existing body of

knowledge that integrates the supporting database with the decision-making

framework to support decision makers in making decisions about DW management in

urban redevelopment projects. Accordingly, within the GIS-based system, a platform


of DW information is created and updated before and during the demolition process,

which is very helpful in urban redevelopment DW management. In addition, the

suggestions of action plans for improving DW management decision-making were

sourced from experienced and knowledgeable experts. Furthermore, the research

findings can be served as a reference for other developing countries that have similar

urban redevelopment contexts as Vietnam.

7.7 SUMMARY

This chapter discussed the findings from the four main research stages, namely the

literature review, survey study, interview study, and finally case study, which were

integrated into the finalised decision-making framework. The background literature

provided a strong basis for developing the conceptual framework, by accounting all

the five sustainability aspects including technical, environmental, economic, social,

and institutional. The insight and perspectives of the five respondent groups in the

survey study were analysed to identify 24 critical factors for efficient decision-making.

Semi-structured interviews were carried out to identify each critical factor thoroughly

while framing action plans in order to improve Vietnamese urban redevelopment DW

management decision-making. The multi-criteria analysis in the survey and interview

study validated the conceptual framework, which is argued can improve DW

management toward more sustainable urban redevelopment in Vietnam. In addition,

based on the critical factors identified by quantitative analysis and the action

plans explored by qualitative analysis, six critical factors were further analysed and

computerised to develop the supporting database for DW management decision-

making. The supporting database included spatial and attribute information of urban

redevelopment DW management at district level.

The research findings were finalised to form the decision-making framework by

integrating the validated framework and supporting database of DW management.

From a practical perspective, the finalised decision-making framework can provide

comprehensive and multi-criteria references with both spatial and attribute information

for decision makers in urban redevelopment DW management at district level.

183

Chapter 8: Conclusion

8.1 INTRODUCTION

Demolition waste is a critical environmental issue for the construction industry. Both

developed and developing countries are facing challenges in the form of urban

redevelopments that generate large amounts of DW. The demolition of existing

buildings is a predominant feature of urban redevelopment and therefore its waste

management is particularly important. However, there is still a lack of accurate

construction waste data, especially in developing countries (Wu, et al., 2014). This

may be due to the focus of previous research on both construction waste and

demolition waste, leading to a gap in the understanding of DW, particularly that of

urban redevelopment projects. Furthermore, there are many challenges in managing

urban redevelopment DW due to the complexities involved, such as poor waste

management planning, the overlapping of responsibilities and ineffective time and cost

management (Lu, Lau, & Poon, 2009; Wu, Yu, Shen, & Liu, 2014). The above issues

warrant the research presented in this dissertation to promote sustainability and

improve urban redevelopment DW management by establishing a decision-making

framework tailored to the Vietnamese urban redevelopment context.

This chapter outlines the achievement of the stated research objectives, presents an

overview of the research conclusion, highlights the research contributions and

limitations, and finally recommends the implications for future research.

8.2 REVIEW OF RESEARCH OBJECTIVES AND DEVELOPMENT PROCESSES

The aim of this research was to develop a comprehensive decision-making framework

for improving DW management in Vietnamese urban redevelopment projects at the

district level. Three main objectives were established in order to achieve the research

aim, as follows:

(1) To explore the current DW management in urban redevelopment projects and

in the context of Vietnam.

184 Chapter 8: Conclusion

(2) To identify critical decision-making factors of DW management in urban


(3) To develop a decision-making framework and critical supporting information

to assist decision makers in improving demolition waste management in

Vietnamese urban redevelopment projects at the district level.

These research objectives serve as a guide throughout the entire research process

(Figure 3-3) in order to achieve the research aim. A mixed method was employed in

this research, applying three different methods to answer the research questions and

achieve the research objectives. The research methods adopted correlating research

objectives are presented in Table 8-1.

The achievement of the first research objective is the domain of information related to

urban redevelopment DW management on a global scale and in the context of Vietnam

(presented in Chapter 2). Based on this useful information, the research gaps were

identified and the list of 53 research decision-making factors was formulated.

Accordingly, the conceptual framework was investigated in the literature review

process (Figure 2-11, Chapter 2).

Table 8-1: The research design related to research objectives

Research objectives Methods Tools

Exploring the current DW management in urban redevelopment projects and in the context of Vietnam

- Literature review

- Document

review

Identifying critical decision-making factors of DW management in urban redevelopment projects at the district level

- Questionnaire

survey - Interview

- Quantitative

analysis - Qualitative

analysis Developing a decision-making framework

and critical supporting information to assist decision makers in improving demolition waste management in Vietnamese urban redevelopment projects at the district level

- Case study

- Quantitative

analysis - GIS-Based

The second objective was designed to answer research questions one and two, which

are, ‘what are the key decision-making factors influencing demolition waste

management in Vietnamese urban redevelopment projects? And how do the key

decision-making factors influence demolition waste management in Vietnamese urban

185

redevelopment projects?’ The survey and the interview study were conducted to

achieve the second research objective (presented in Chapters 4 and 5). Subsequently,

a list of 24 critical factors was identified and the conceptual framework was then

revised (Figure 4-2). In addition, the action plans were synthesised from the

interviewees’ suggestions for improving DW management in Vietnamese urban


Based on the results achieved from the previous study, a case study was conducted in

order to identify the crucial information that is needed for DW management decision-

making in urban redevelopment projects (presented in Chapter 6). The supporting

database was integrated in a GIS-based model to address the third research question:

What is the necessary information to support key stakeholders in demolition waste

management in Vietnamese urban redevelopment projects at the district level? The

integration of the proposed decision-making framework and the supporting database

was finally developed to achieve the third research objective (Figure 7-1 in Chapter

7).

8.3 DECISION-MAKING FRAMEWORK FOR IMPROVING DEMOLITION WASTE MANAGEMENT IN VIETNAMESE URBAN REDEVELOPMENT PROJECTS

The aim of this research has been fulfilled and a decision-making framework has been

developed that is argued to improve DW management in Vietnamese urban

redevelopment projects. The research conclusions synthesised from the key findings

reported in the previous chapters are presented in the following sections.

8.3.1 The factors influencing demolition waste management in Vietnamese urban redevelopment projects

In the context of Vietnam, there is a lack of regulation supporting DW management in

the Vietnamese construction industry, especially in urban redevelopment projects. In

addition, obtaining reliable data on C&D waste is not easy, as data in this discipline is

often managed together with municipal waste data, which makes it difficult to

precisely estimate the amount of DW in urban redevelopment projects.

Based on the literature review, 53 research factors that have the potential to improve

DW management in urban redevelopment projects in Vietnam were investigated. The

wording of these factors was essentially based on the comprehensive review of related


knowledge acquired from the literature review. The relevant literature for each factor

was presented in Table 2-2 in Chapter 2, which represents a wide range of experiences

from researchers and practitioners in different countries and regions. It is important to

identify the most influencing factors for the context of Vietnamese urban

redevelopment. It is noteworthy that the concept of sustainable urban redevelopment

is embedded in the research factors, which were categorised into five categories:

technical, environmental, economic, social, and institutional.

The findings from the literature review were used as a baseline for developing the

questionnaires in the survey study. A questionnaire survey was adopted to investigate

the critical factors, which are of significant concern among key stakeholders in making

decisions about DW management in the context of Vietnamese urban redevelopment

projects. The survey was designed on the basis of 53 decision-making factors

identified in the literature review. Five groups of respondents that have been working

in the field of DW management in Vietnamese urban redevelopment projects were the

targeted key stakeholders from different organisations in three main cities in Vietnam

(Hanoi, Hai Phong, and Ho Chi Minh City), including academics, planners,

consultants, engineers, and policy makers. The respondents were asked to rank the

level of importance of each factor based on their knowledge and experience.

The quantitative analysis revealed 24 critical factors that have a significant influence

on improving DW management in Vietnamese urban redevelopment projects

(presented in Table 4-9, Chapter 4). Interestingly, three critical factors (training of DW

management, cost estimation of waste transport, and the uniqueness of DW),

represented significant differences between respondents’ perspectives. Thus, the

conceptual framework was revised based on identified 24 critical factors which were

categorised into five categories related to sustainability (presented in Figure 4-2 in

Chapter 4).

The top-five critical factors in the rankings were in the categories of institutional and

technical, wherein three factors were in the institutional category: providing guidelines

of DW management plan, regular information update, and understanding of

stakeholders’ responsibilities, which were ranked first, third, and fifth respectively.

This echoes the notion that the right decision can be made if the institutional factors

that contribute to effective DW management are considered. In this light, Yuan (2013)

also indicates that the lack of accurate regulations of C&D waste is one of the reasons

187

for the poor C&D waste management. Therefore, accomplishing policies and strategies

will help decode the problems, which are too general or not detailed enough for

implementing DW management in urban redevelopment projects.

In addition, updated and accurate information of DW is required for essential

communication among stakeholders in effective urban redevelopment DW

management. In support of this finding, Shen, et al. (2007) provide a tool to enable

stakeholders to access the project information and share the knowledge and

information while working together towards better project performance.

Consequently, this research developed a GIS-based model for storing and displaying

the supporting database to aid decision-making in this area. Furthermore, the

misalignment of stakeholder responsibilities in C&D waste management is another

contributing factor hindering better C&D waste management practice (Yuan, 2013).

Thus, it is significant finding to identify who needs to participate in the construction

waste management process (Manowong, 2012).

Two other critical factors of the top five in the rankings were in the technical category,

including on-site sorting and determining the DW management procedures, which

were ranked second and fourth respectively. It is of note that on-site sorting, when

effectively implemented, can assist the contractors in arranging and using materials

properly (Wu & Ann, 2014). Thus, this factor, together with the factor of waste

estimation, needs to be seriously considered in DW management, as it can be used to

develop the DW database. In addition, defining C&D waste management procedure

should also be seriously considered in effective waste management planning,

particularly scheduling before construction activities (Poon, et al., 2001). Thus, this

finding suggests there is a need for a detailed and comprehensive plan of C&D waste

management to achieve waste minimisation and a high level of recycling waste

(Yeheyis, et al., 2013; Yuan, 2013).

Regarding environmental performance, six critical factors were determined as an

important influence on urban redevelopment DW management. To be specific, the

factor of ‘promotion of 3R in DW management’ was explored as the most important

factor in the environmental category and was ranked eighth of all given factors. The

reason for promoting 3R strategies is offering the benefits in reducing the use of raw

materials and converting more recyclable from the landfills (Abbas, et al., 2006).


These strategies were considered by Peng, et al. (1997), as an important factor in

choosing waste management measures. Moreover, the second environmental factor,

‘stakeholder awareness’ was ranked twelfth in the rankings. This resonates with the

confirmation that this factor proves valuable in waste minimisation through changing

practitioners’ attitudes towards waste generation, classification, recycling and disposal

(Manowong, 2012; Osmani, et al., 2008).

Regarding economic performance, three critical factors were considered to have an

important influence on urban redevelopment DW management. The first economic

factor was ‘cost-effective demolition plan’, which was ranked seventh in the rankings.

This factor is broadly considered as an important factor of a successful and sustainable

C&D waste management (Wang, et al., 2004). Regarding social performance,

“preservation of natural resources, cultural, and heritage” was one of the only two

social critical factors, which was ranked sixth. Broadly, this factor is defined by Chan

and Lee (2008b) as one of the most considered urban design factors in attaining

sustainability in urban renewal.

In conclusion, the rankings of the critical factors of the research suggested a strong

relationship to all five aspects of sustainability in urban redevelopment DW

management. Through the survey data analysis, the first research question was

addressed by identifying 24 critical factors that significantly influence DW

management in urban redevelopment in Vietnam.

8.3.2 Action plans for improving demolition waste management in Vietnamese urban redevelopment projects

The interviewees in the interview study were asked to provide their comments on how

influential each critical decision-making factor is, in improving DW management in

Vietnamese urban redevelopment projects, and what action is required to improve DW

management in relation to each factor. The qualitative approach was selected as a tool

to analyse interview results to sort out the action plans suggested by interviewees.

Results from this method affirmed that the second research question was addressed,

which was “how do the key decision-making factors influence demolition waste

management in Vietnamese urban redevelopment projects?”

Similarly, to the questionnaire participants, the interviewees represented five key

stakeholder groups. Among the 22 interviewees, four were researchers, three were

planners, three were consultants, five were engineers and seven were policy makers.

189

All the interviewees generally agreed that the proposed framework covered the major

factors. These 24 critical factors were confirmed by the interviewees as important

factors in improving DW management in Vietnamese urban redevelopment projects;

therefore, should be considered to improve DW management in Vietnamese urban

redevelopment projects. The findings from the interview study were analysed as

possible actions of improving urban redevelopment DW management in Vietnam,

which were grouped into 15 main themes of critical factors (presented in Table 5-4,

Chapter 5).

With regard to the five themes of technical performance, eleven action planning areas

were suggested by interviewees to improve DW management in Vietnamese urban

redevelopment projects. One engineering manager emphasised that technology leads

to the reduction of DW and the improvement of the waste classification. However,

there is a need for government support and consultation in ‘choosing demolition

methods’, particularly, the application of environmentally-friendly technology.

Defining clearly DW management procedures in the early stage of demolition work

was the action plans suggested for the theme of ‘DW management procedures’.

Interview findings also related to the theme of ‘waste classification and estimation’.

First, interviewees suggested the classification of DW should be implemented on-site

of the demolition. In order to encourage on-site waste classification, waste sorting

should be improved and the use of recycled materials should be promoted. In addition,

DW estimation can be a prerequisite of DW management that should be considered

before the demolition stage. Subsequently, the DW information could assist decision

makers and contractors in planning waste classification and waste recycling.

The theme of ‘planning for landfill, sorting area, and storage’ received attention from

the interviewees and suggested DW management including giving priority to landfills

and transfer station planning; identifying suitable sites for transfer stations and

landfills was considered important. From these, identifying suitable landfill sites and

transfer stations appears to be needed in order to develop DW delivery plans and

reduce costs for DW transport, particularly for the large-scale DW volume from

different urban redevelopment projects at the district level. ‘Training’ was considered

as an important factor in improving urban redevelopment DW management. Providing

appropriate training courses in DW management and demolition technology was


proposed in order to advance stakeholders’ skill levels in demolition and waste

classification, particularly skill in capturing the benefits of low waste technology. Such

training raises the stakeholder awareness of DW management and waste classification.

Seven action plans relating to the four themes of environmental performance were

conveyed by interviewees to improve DW management in Vietnamese urban

redevelopment projects. In order to raise stakeholder awareness, interviewees

suggested the government should promulgate C&D waste policies to encourage

stakeholder engagement in urban redevelopment DW management. In addition,

identifying the DW characteristics in the early stage is crucial to understand what type

of DW is contained in the building to be demolished. This, together with the

‘promotion of 3R strategies’ and policies in increasing reuse and recycled waste, could

increase waste recovery rate and minimise DW disposal in the landfill. Regulating

strict environmental policies was also suggested to ensure there was an obligation in

the implementation of ‘environmental impact assessment’ for each urban

redevelopment project in order to address the environmental impacts associated with

DW management.

Two action plans were recommended by interviewees for the theme of economic

performance, which are the development of cost-effective scenarios and cost

estimation for specific stages of DW management. The information of cost analysis of

DW management could help decision makers select the most effective DW

management scenarios, and save costs of DW collection, DW transport, DW recycling,

and DW disposal. Regarding two themes of social performance, two action plans were

nominated, which are the integration of ‘preservation’ into DW management and

prioritising the ‘community’s safety’ in the project’s objectives. These require the

stakeholders to pay attention to environmental protection and the quality of a

neighbourhoods’ life in DW management.

Nine action plans relating to the three themes of institutional performance were

suggested by interviewees to improve DW management in Vietnamese urban

redevelopment projects. Interviewees suggested providing the best practice guidelines

to assist all stakeholders and encourage the development of a deep understanding of

the procedures of DW management, their responsibilities, and the institutional

arrangement in DW management. In addition, in order to improve the stakeholder

engagement, it was suggested the government should take the leading role in DW

191

management, and also highlighted was the importance to incorporate the sustainability

element in DW management regulations to encourage stakeholders to get more

involved in DW management in urban redevelopment projects. Developing the DW

database and regular reporting were suggested with a view to improving the

‘communication’ among stakeholders. These would also help stakeholders efficiently

communicate and share information in the pre-demolition stage, during the demolition

stage, and in the post-demolition stage.

In conclusion, interviewees supported the claim that all 24 critical factors play an

important role in improving DW management in Vietnamese urban redevelopment

projects. In addition, the action plans suggested by the interviewees supported six

identified critical factors that could be used to develop the DW database and improve

the DW management decision-making process.

8.3.3 Supporting database for urban redevelopment demolition waste management decision-making process

The interview results identified six critical factors that can provide valuable support

for decision makers in the DW management decision-making process in urban

redevelopment projects, including (1) on-site sorting, (2) rate of waste recovery, (3)

cost-effectiveness demolition plan, (4) estimation of DW, (5) cost estimation of waste

transport, and (6) landfill planning. A case study was conducted to define the six above

critical factors to fulfil the factor of ‘information update’, which was ranked as the

third critical factor in the rankings (presented in Figure 7.1, Chapter 7).

In order to support the DW management decision-making process in urban

redevelopment projects, essential information was collected to develop a supporting

database. The information from the four projects in this case study is shown in Table

6-1, Chapter 6. There are two sources from where the data is collected.

The process of the supporting database development included three steps as follows.

First, the collected attribute data were calculated through Excel software. Second, the

spatial data were processed through ArcGIS software, to be integrated and linked with

the attribute data. Finally, the crucial data information was stored in the form of map

layers.


Subsequently, the volume of DW and its components were estimated (presented in

Appendix D). The DW estimation was calculated for each type of DW (brick, mortar,

concrete, and metal) and the total of DW in four projects. The GIS maps were used to

integrate the data of DW with each building and each project (presented in Figure 6-4

and 6-6, Chapter 6). It is argued in this thesis, that this information can assist decision

makers in planning demolitions, estimating DW management cost-effectiveness and

can potentially save time in decision-making relating to the reuse and recycling of

construction waste.

In addition, based on the total volume of inert DW, including brick, mortar, and

concrete, the number of pick-up trucks was calculated (presented in Figure 6-7).

Accordingly, decision makers and contractors could plan an effective DW transport

plan that could help reduce the time and the cost of transport. Furthermore, based on

the number of C&D waste landfill sites in Hanoi, the landfill site capacity per day, and

landfill site locations, the scenarios of choosing suitable landfill were presented in

Figure 6-8. It is argued that this approach can assist decision makers analyse the cost-

effectiveness of DW transport.

The case study provided useful information for decision makers in DW management

in urban redevelopment projects in the areas of waste estimation, waste classification,

waste transport, and selection of landfill sites. In addition, the case study demonstrated

the possibility for project managers to update DW management information to allow

all stakeholders to access and communicate throughout the DW management process.

Subsequently, the decision-making framework for improving DW management in

Vietnamese urban redevelopment projects was developed based on the integration of

24 critical factors and the supporting database (presented in Figure 7-1, Chapter 7).

8.4 RESEARCH CONTRIBUTIONS

The ultimate contribution of the research is suggesting a decision-making framework

consisting of key decision-making factors, and a database to assist the decision-making

process of DW management in Vietnamese urban redevelopment projects. The holistic

consideration of sustainable aspects and extensive participation of key stakeholders

makes it possible to contribute to both academia and industry practice.

193

8.4.1 Contribution to academic knowledge

(1) Improving the current literature of demolition waste management in urban

redevelopment projects in developing countries

DW management has received much attention over the last two decades as one of the

main indicators of sustainable construction. However, the literature review revealed

that there is a general lack of research effort relating to DW management in urban

redevelopment projects. Although the current literature provides a broader coverage

of C&D waste management in the construction industry, it does not focus specifically

on DW management, particularly in the field of urban redevelopment in developing

countries. This research identified four main knowledge gaps and recommendations

for future research were offered in the developing countries context, namely:

stakeholder engagement, decision support, environmental challenges, strategy and

solutions, and performance evaluation.

(2) Providing new knowledge in the decision-making process of DW management

in urban redevelopment projects with a focus on sustainability.

As an early contribution, this research addressed the identified research gaps and

provides a holistic interpretation of important decision-making factors to be considered

in DW management in the urban redevelopment projects, particularly in developing

countries. There was no previous research pertaining to a holistic view of the decision-

making process for improving DW management in urban redevelopment projects. All

of the research factors were sparsely studied in different research projects within the

field of urban redevelopment DW management. However, these factors were complex

and strongly linked to sustainability. In this research, the sustainability thinking is

embedded in the affecting factors represented as multi-criteria for improving DW

management, where technical, environmental, economic, social, and institutional

aspects overlap.

In this research, the critical factors were identified based on the consensus of key

stakeholders in DW management in Vietnamese urban redevelopment projects,

namely academics, planners, consultants, engineers, and policy makers. Therefore,

the research contributes to new knowledge of multiple stakeholders’ perspectives on

the critical decision-making factors for improving DW management in urban

redevelopment projects. The comparative analysis provides the platform to balance


five aspects of sustainable urban redevelopment and identifies consensual critical

decision-making factors for improving DW management. The research findings

provide a strong foundation for other researchers investigating DW management in

developing countries, particularly related to the identified factors influencing DW

management in urban redevelopment projects at different levels.

The case study incorporating the GIS-based model also provides a new knowledge in

developing a support system and the associated information for making DW

management decision in urban redevelopment projects. This finding helps decision

makers take into account multiple criteria in the decision-making process, which

involves both spatial and attribute database.

8.4.2 Contribution to the industry practice

(1) Implications for the demolition waste management participants

The involvement of five key stakeholder groups in the questionnaire survey and the

interview study provides a unique contribution in understanding different practitioner

perspectives on factors affecting DW management in urban redevelopment projects.

The critical factors encompassed all five aspects of sustainable project performance,

including technical, environmental, economic, social, and institutional. These results

can potentially assist specific stakeholders to increase their awareness of sustainability

and to solve problems associated with DW management.

Research results relating to the influencing factors suggest that a sustainable approach

is essential in improving the overall performance of DW management in complex

urban redevelopment projects, particularly in developing countries. The proposed

approach could benefit stakeholders in terms of improving communication, sharing

information, and understanding roles in DW management in urban redevelopment

projects.

The decision-making framework also included a supporting database that is argued to

provide stakeholders with necessary DW information to support in the decision-

making process in urban redevelopment projects. This new approach contributes to

improving the planning for reuse and recycling of DW, particularly considering the

size and scale of urban redevelopment projects at a district level. In addition, the GIS-

based model was integrated in decision-making framework to provide a visual

representation and quantification of the DW flow from demolition work.

195

(2) Implications for the construction industry

In previous research, DW is often managed in a piecemeal way without appropriate

consideration of the broader sustainability implications. The decision-making

framework was proposed based on the five aspects of sustainability from the

perceptions of the five key stakeholders (academics, planners, consultants, engineers,

and policy makers) through survey and interview study in Vietnam. This framework

offers significant benefits in addressing sustainability issues associated with urban

redevelopment DW in developing countries. The list of 24 critical factors related to

the decision-making process may be used as key criteria in evaluating DW

management performance towards sustainable urban redevelopment in Vietnam.

The critical decision-making factors enable stakeholders to better understand the isues

influencing DW management. Also, the integration of decision-making factors and

supporting database in the proposed framework can be used to facilitate the

stakeholder buy-in and involvement in implementing urban redevelopment DW

management strategy. This can help stakeholders in considering priority issues in

implementing DW management. In addition, the supporting database provides

stakeholders with the crucial information of DW management in assessing the cost and

plan effectiveness.

Further, a key implication of the research is related to the need of stakeholders in taking

a holistic approach to managing DW in a large scale urban redevelopment projects.

Particularly, the GIS-based tool might be applied as a decision support tool to create a

platform for more detailed DW database. This is expected to improve the quality of

information available to stakeholders and encourage more information shared in urban

redevelopment projects on a large scale.

It is recommended that critical decision-making factors should be considered by

Vietnam government in their strategies of developing industry-wide construction and

formulating DW management policies towards sustainable urban redevelopment.

8.5 RESEARCH LIMITATIONS

This research developed a decision-making framework including a supporting

database to improve DW management in Vietnamese urban redevelopment projects.

This research took a multi-criteria approach to sustainability within this research


context. Despite the significant contribution of the research, there are research

limitations that need to be acknowledged to provide opportunities for future research.

The key limitations of the study were:

Although research samples involved industry practitioners and experts in the

field of urban redevelopment DW management, they varied in experiences and

perspectives. Further, research samples may not represent the entire industry

practitioners and academics in Vietnam. Therefore, larger sample sizes within

the five groups would provide improved external validity to the research

results.

The buildings to be demolished in all four case study projects dated back over

40 years. The structure design was hand-drawn and was hard to source. In

addition, the structure of units has been illegally altered and expanded by

residents. Efforts were made to check the accuracy of the sites and building

layouts to mitigate risk of errors relating to building information.

The DW estimation was only calculated for four main DW components.

Further estimation of some other materials, such as plastic and wood, should

be calculated, which would provide useful information for DW management

and recycling strategies.

The cost of DW transport was analysed based only on the distances to the

landfills due to time and resource constraints. Further research should take into

account other factors, such as disposal fees, or time consumed for waste

transport.

Given that this research only focused on DW management in Vietnamese urban

redevelopment projects, this may limit the ability to generalise other research

context. However, the research results are likely to apply in similar projects in

other similar developing countries in consideration of increasing urban

redevelopment trends and the economic and policy contexts.

8.6 RECOMMENDATIONS FOR FUTURE RESEARCH

In light of the research findings and research limitations, future research projects are

proposed as follows. Firstly, key related literature revealed that other developing

countries may encounter similar issues relating to DW management in urban

redevelopment projects. Although this research focuses on Vietnamese urban

197

redevelopment projects, this research also references the experience from both

developed and developing countries to contribute to the development of the proposed

decision-making framework. Therefore, it is recommended that this framework should

be further tested in similar developing countries, such as China, India, or Brazil. This

may improve the validity of the framework outside the chosen research context and

increase its generalisability. This future research may entail adapting the decision-

making framework to those countries by taking their specific regulations, cultural and

political environments into consideration.

Although many social factors are considered as important factors in urban

redevelopment projects, the social factors for improving urban redevelopment DW

management were ranked relatively low by five stakeholder groups in the study. These

included relatively low rankings for ‘the role of community in decision-making

process’, ‘increasing of public awareness’, and ‘job creation’. It is recommended

future studies focus on the social decision-making factors that influence DW

management in urban redevelopment projects. In addition, further investigation will

enhance the reasons to why social factors may be considered less important in DW

management decision-making in developing countries, like Vietnam.

The DW management process comprises different stages, such as DW collection, DW

classification, DW transport, and DW disposal. Cost analysis for the entire DW

management process might provide useful information to assess the cost-effectiveness

of the DW management plan. In the case study, this research focused on only the

number of pick-up trucks and distances to the landfills in the DW transport cost

analysis. Therefore, a general recommendation is that more research is required to

consider further information for cost analysis of collecting, sorting, and disposal of

DW in urban redevelopment projects. As a result, the cost-benefit analysis would be

more useful for decision makers in considering the economic performance of DW


In this research, the volume of DW generation was estimated by waste weight per area

method, which was first reported in the study by Yost and Halstead (1996). In addition,

insufficient information of demolished buildings may affect the accuracy of DW

estimation. It is recommended that future research should concentrate on improving

the quality of data input for the DW estimation, particularly for all types of DW.


Accordingly, further research could consider a comprehensive collection of building

information for DW estimation. It is expected the increased accuracy of the DW

information can assist decision makers to increase the rate of DW recovery and

minimise the environmental impacts.

Finally, this study was undertaken with a focus on developing the GIS-based model

for supporting decision makers via quantitative analysis. It is recommended that the

GIS model and other tools such as BIM could be deployed in future research for

capturing and sharing the database for not only project or district level, but also

potentially at a city and national level. The revised model with more accurate input

data in supporting DW management and validating the proposed framework will be

developed upon this research and further enhance the information available to decision

makers in the sustainable delivery of urban redevelopment projects.

Bibliography 199

Bibliography

Abbas, A., Fathifazl, G., Isgor, O., Razaqpur, A., Fournier, B., & Foo, S. (2006). Environmental benefits of green concrete. In EIC Climate Change Technology, 2006 IEEE (pp. 1-8): IEEE.

Adams, D., & Hastings, E. (2001). Urban renewal in Hong Kong: transition from

development corporation to renewal authority. Land Use Policy, 18(3), 245-258.

Adams, J., Khan, H. T., Raeside, R., & White, D. I. (2007). Research methods for

graduate business and social science students: SAGE publications India.

Ahuja, V., Yang, J., & Shankar, R. (2010). IT-enhanced communication protocols for

building project management. Engineering, Construction and Architectural Management, 17(2), 159-179.

Akintoye, A. (2000). Analysis of factors influencing project cost estimating practice.

Construction Management & Economics, 18(1), 77-89.

Akintoye, A. S., & MacLeod, M. J. (1997). Risk analysis and management in

construction. International journal of project management, 15(1), 31-38.

Al-Saggaf, A., & Jrade, A. (2015). Benefits of integrating BIM and GIS in construction

management and control.

Andersen, H. S. (2003). Urban Sores. On the interaction between segregation, urban

decay and deprived neighbourhoods: Ashgate.

Arthurson, K. (1998). Redevelopment of public housing estates: the Australian

experience. Urban Policy and Research, 16(1), 35-46. doi:DOI:

10.1080/08111149808727746

Begum, R. A., Siwar, C., Pereira, J. J., & Jaafar, A. H. (2006). A benefit–cost analysis

on the economic feasibility of construction waste minimisation: the case of Malaysia. Resources, Conservation and Recycling, 48(1), 86-98.

Benjamini, Y., & Hochberg, Y. (1995). Controlling the false discovery rate: a practical

and powerful approach to multiple testing. Journal of the royal statistical society. Series B (Methodological), 289-300.

200 Bibliography

Berg, B. L. (2004). Methods for the social sciences: Pearson Education Inc, United

States of America.

Bernt, M. (2009). Partnerships for demolition: The governance of urban renewal in East

Germany's shrinking cities. International Journal of Urban and Regional Research, 33(3), 754-769.

Biddle, D. (2001). Deconstruction industry'demolishes' the alternative. In Business,

23(3), 27-27.

Bjerregaard, M. (2008). Demolition waste: are we doing our best? In Proceedings of the

Institution of Civil Engineers-Waste and Resource Management (Vol. 161, pp. 45-49): Thomas Telford Ltd.

Blaxter, L. (2010). How to research: McGraw-Hill Education (UK).

Blengini, G. A. (2009). Life cycle of buildings, demolition and recycling potential: a

case study in Turin, Italy. Building and environment, 44(2), 319-330.

Bowie, J., Farfel, M., & Moran, M. H. (2005). Community experiences and perceptions

related to demolition and gut rehabilitation of houses for urban redevelopment. Journal of Urban Health, 82(4), 532-542. doi:10.1093/jurban/jti075

Brodersen, J., Juul, J., Jacobsen, H., & Tsotsos, D. (2002). Review of selected waste

streams. Retrieved from http://www.eea.europa.eu/publications/technical_report_2001_69

Brooks, K. A., Adams, C., & Demsetz, L. A. (1994). Germany's construction and

demolition debris recycling infrastructure: what lessons does it have for the US. Sustainable construction, 16, 647-656.

Broudehoux, A.-M. (1994). Neighborhood regeneration in Beijing: An overview of

projects implemented in the inner city since 1990. Mcgill University.

Bryman, A., & Bell, E. (2015). Business research methods: Oxford University Press,

USA.

Bryson, J. M., & Bromiley, P. (1993). Critical factors affecting the planning and

implementation of major projects. Strategic Management Journal, 14(5), 319-337.

Bibliography 201

Cavana, R. Y., Delahaye, B. L., & Sekaran, U. (2001). Applied business research: Qualitative and quantitative methods: John Wiley & Sons Australia.

Chalkias, C., & Lasaridi, K. (2011). Benefits from GIS based modelling for municipal

solid waste management. In Integrated Waste Management-Volume I: InTech.

Chan, A. P., Scott, D., & Chan, A. P. (2004). Factors affecting the success of a

construction project. Journal of construction engineering and management, 130(1), 153-155.

Chan, E., & Lee, G. K. (2008a). Critical factors for improving social sustainability of

urban renewal projects. Social Indicators Research, 85(2), 243-256.

Chan, E. H., & Lee, G. K. (2008b). Contribution of urban design to economic

sustainability of urban renewal projects in Hong Kong. Sustainable Development, 16(6), 353-364.

Changyong, F., Hongyue, W., Naiji, L., Tian, C., Hua, H., & Ying, L. (2014). Log-

transformation and its implications for data analysis. Shanghai archives of psychiatry, 26(2), 105.

Chen, X., & Lu, W. (2017). Identifying factors influencing demolition waste generation

in Hong Kong. Journal of cleaner production, 141, 799-811.

Cheng, J. C., & Ma, L. Y. (2013). A BIM-based system for demolition and renovation

waste estimation and planning. Waste management, 33(6), 1539-1551.

Cooke, S., & Slack, N. (1991). Making management decisions. New York: Prentice

Hall.

Corbin, J., Strauss, A., & Strauss, A. L. (2014). Basics of qualitative research: Sage.

Couch, C. (1990). Urban renewal: theory and practice: Macmillan.

Couch, C., & Dennemann, A. (2000). Urban regeneration and sustainable development

in Britain: The example of the Liverpool Ropewalks Partnership. Cities, 17(2), 137-147.

Couch, C., Sykes, O., & Börstinghaus, W. (2011). Thirty years of urban regeneration in

Britain, Germany and France: The importance of context and path dependency. Progress in Planning, 75(1), 1-52.

202 Bibliography

Creswell, J. (2009). Research design: Qualitative, quantitative, and mixed methods

approaches: SAGE Publications, Incorporated.

Creswell, J. W. (2013). Research design: Qualitative, quantitative, and mixed methods

approaches: Sage publications.

Creswell, J. W., & Plano Clark, V. (2011). Choosing a mixed methods design.

Designing and conducting mixed methods research, 53-106.

Darren, G., & Mallery, P. (1999). SPSS for Windows Step by Step: A simple guide and

reference. Needham Heights, MA: Allyn & Bacon.

De Benedetto, L., & Klemeš, J. (2009). The Environmental Performance Strategy Map:

an integrated LCA approach to support the strategic decision-making process. Journal of Cleaner Production, 17(10), 900-906.

De Sousa, C. A. (2008). Brownfields redevelopment and the quest for sustainability

(Vol. 3): Emerald Group Publishing.

Deilmann, C., Effenberger, K.-H., & Banse, J. (2009). Housing stock shrinkage:

vacancy and demolition trends in Germany. Building Research & Information, 37(5-6), 660-668.

del Río Merino, M., Azevedo, I. S. W., & Gracia, P. I. (2009). Sustainable construction:

construction and demolition waste reconsidered. Waste management & research, 28, 118-129. doi:10.1177/0734242X09103841

Delmas, M., & Toffel, M. W. (2004). Stakeholders and environmental management

practices: an institutional framework. Business strategy and the Environment, 13(4), 209-222.

Demberel, E. (2010). Strategies for the sustainable redevelopment of residential

buildings in Ulaanbaatar, Mongolia Master. RMIT University, Melbourne, Australia.

Diaz, L., Savage, G., & Golueke, C. (1996). Sustainable community systems: the role of

integrated solid waste management. In International Madison Waste Conference Municipal and Industry Waste (pp. 280-291): Department of Engineering Professional Development

Bibliography 203

Dieu, T. (2017, June 21, 2017). The issues of urban redevelopment in Ho Chi Minh city. Retrieved from http://vietnamnet.vn/vn/bat-dong-san/du-an/cai-tao-chung-cu-cu-tp-hcm-ngay-cang-xa-roi-muc-tieu-363656.html

Ding, T., & Xiao, J. (2014). Estimation of building-related construction and demolition

waste in Shanghai. Waste Management, 34(11), 2327-2334.

Do, H. (2017). Hai Phong urban redevelopment plan. Retrieved from

https://baomoi.com/hai-phong-thao-do-hang-loat-nha-tap-the-cu-nat-xay-dung-chung-cu-cao-tang/c/24164923.epi

Dowall, D. E. (1994). Urban residential redevelopment in the People's Republic of

China. Urban Studies, 31(9), 1497-1516.

Dutton, J. E. (1993). Interpretations on automatic: A different view of strategic issue

diagnosis. Journal of Management Studies, 30(3), 339-357.

Elbanna, S. (2006). Strategic decision‐making: Process perspectives. International

Journal of Management Reviews, 8(1), 1-20.

Ercan, M. A. (2011). Challenges and conflicts in achieving sustainable communities in

historic neighbourhoods of Istanbul. Habitat International, 35(2), 295-306. doi:https://doi.org/10.1016/j.habitatint.2010.10.001

EUROSTAT. (2017). Waste statistics. Retrieved July 20, 2017

http://ec.europa.eu/eurostat/statistics-explained/index.php/Waste_statistics#Total_waste_generation

Fang, K., & Zhang, Y. (2003). Plan and market mismatch: Urban redevelopment in

Beijing during a period of transition. Asia Pacific Viewpoint, 44(2), 149-162. doi:10.1111/1467-8373.00190

Farfel, M. R., Orlova, A. O., Lees, P. S., Rohde, C., Ashley, P. J., & Chisolm, J. J.

(2005). A study of urban housing demolition as a source of lead in ambient dust on sidewalks, streets, and alleys. Environmental research, 99(2), 204-213. doi:10.1016/j.envres.2004.10.005

Fatta, D., Papadopoulos, A., Avramikos, E., Sgourou, E., Moustakas, K., Kourmoussis,

F., . . . Loizidou, M. (2003). Generation and management of construction and demolition waste in Greece—an existing challenge. Resources, Conservation and Recycling, 40(1), 81-91. doi:10.1016/S0921-3449(03)00035-1

204 Bibliography

Fellows, R. F., & Liu, A. M. (2015). Research methods for construction: John Wiley & Sons.

Field, A. (Singer-songwriter). (2014). Factor Analysis Using SPSS. Research Methods

II. On.

Fong, P. K. (1985). Issues in urban redevelopment: the Land Development Corporation.

Built Environment (1978-), 283-293.

Formoso, C. T., Soibelman, L., De Cesare, C., & Isatto, E. L. (2002). Material waste in

building industry: main causes and prevention. Journal of construction engineering and management, 128(4), 316-325.

Fredrickson, J. W. (1985). Effects of decision motive and organizational performance

level on strategic decision processes. Academy of Management journal, 28(4), 821-843.

Fung, A. (2004). Sustainable development and the conservation of natural and cultural

heritage. Sustainable development in Hong Kong, 387-420.

García‐Arenzana, N., Navarrete‐Muñoz, E. M., Lope, V., Moreo, P., Vidal, C., Laso‐

Pablos, S., . . . Santamariña, C. (2014). Calorie intake, olive oil consumption and mammographic density among Spanish women. International journal of cancer, 134(8), 1916-1925.

Gephart Jr, R. P. (1991). Multiple methods for tracking corporate social performance:

Insights from a study of major industrial accidents. Research in corporate social performance and policy, 12, 359-383.

Gotham, K. F. (2001). Urban redevelopment, past and present. critical perspectives on

urban redevelopment, 6, 1-31.

Grebler, L. (1964). Urban renewal in European countries: its emergence and potentials:

University of Pennsylvania Press.

Ha, S.-K. (2001). Developing a community-based approach to urban redevelopment.

GeoJournal, 53(1), 39-45.

Habitat, U. (2006). State of the World’s Cities 2006/7. New York: United Nations.

Hain, P. (1980). Neighbourhood participation. London: Temple Smith.

Bibliography 205

Harrison, K. W., Dumas, R. D., Solano, E., Barlaz, M. A., Brill Jr, E. D., & Ranjithan,

S. R. (2001). Decision support tool for life-cycle-based solid waste management. Journal of Computing in Civil Engineering, 15(1), 44-58.

He, S., & Wu, F. (2007). Socio-spatial impacts of property-led redevelopment on

China’s urban neighbourhoods. Cities, 24(3), 194-208.

Hendriks, C., & Pietersen, H. (2000). Sustainable Raw Materials–Construction and

Demolition Waste (165-SRM). State-of-the-Art Report of RILEM Technical Committee.

Hendriks, C. F., & Jansen, G. (2001). Reuse of construction and demolition waste in the

Netherlands for road constructions. HERON, vol. 46 (2), 2001.

Hendriks, C. F., & Janssen, G. (2001). Application of construction and demolition

waste. HERON, vol. 46 (2), 2001.

Hill, R. C., & Bowen, P. A. (1997). Sustainable construction: principles and a

framework for attainment. Construction Management & Economics, 15(3), 223-239.

Hitt, M. A., & Tyler, B. B. (1991). Strategic decision models: Integrating different

perspectives. Strategic management journal, 12(5), 327-351.

Ho, E. C.-m. (2012). Renewing the urban regeneration approach in Hong Kong: Run

Run Shaw Library, City University of Hong Kong.

Hoang, N. (2017). The three important urban redevelopment projects in the Hanoi.

Retrieved from http://cafef.vn/ha-noi-cai-tao-3-khu-chung-cu-cu-tren-dat-vang-the-nao-20170402084818305.chn

Holcomb, H. B. B., Robert A. (1981). Revitalizing Cities: Resource Publications in

Geography.

Huang, W.-L., Lin, D.-H., Chang, N.-B., & Lin, K.-S. (2002). Recycling of construction

and demolition waste via a mechanical sorting process. Resources, Conservation and Recycling, 37(1), 23-37.

Hui, E. C., Wong, J. T., & Wan, J. K. (2008). A review of the effectiveness of urban

renewal in Hong Kong. Property Management, 26(1), 25-42.

206 Bibliography

Hung, M.-L., Ma, H.-w., & Yang, W.-F. (2007). A novel sustainable decision making model for municipal solid waste management. Waste management, 27(2), 209-219.

Huuhka, S., & Lahdensivu, J. (2014). Statistical and geographical study on demolished

buildings. Building Research & Information, 41(1), 73-96. doi:10.1080/09613218.2014.980101

Huy, G. (2015). A holistic view of aging building redevelopment Retrieved from

Vietnam Government Web Portal website: http://thanglong.chinhphu.vn/Home/Cai-tao-chung-cu-cu-can-nhin-tong-the-trong-chinh-trang-do-thi/20159/14591.vgp

Hyder Consulting, E. C. S. R. S. (2011). Construction and Demolition Waste Status

Report. Retrieved from http://www.environment.gov.au/protection/national-waste-policy/publications/construction-and-demolition-waste-status-report

Imrie, R., Lees, L., & Raco, M. (2009). Regenerating London: governance,

sustainability and community in a global city: Routledge.

Itard, L., & Klunder, G. (2007). Comparing environmental impacts of renovated

housing stock with new construction. Building Research & Information, 35(3), 252-267. doi:10.1080/09613210601068161

Jim, C.-Y. (1994). Urban renewal and environmental planning in Hong Kong. The

Environmentalist, 14(3), 163-181.

Johnson, P., & Clark, M. (2006). Business and management research methodologies:

Sage.

Karadimas, N. V., & Loumos, V. G. (2008). GIS-based modelling for the estimation of

municipal solid waste generation and collection. Waste Management & Research, 26(4), 337-346.

Kazemian, A. R. (1991). Urban renewal planning versus local values PhD. Chalmers

University of Technology Göteborg, Sweden

Kibert, C. J. (1994). Establishing principles and a model for sustainable construction. In

Proceedings of the First International Conference on Sustainable Construction (pp. 6-9): Tampa Florida, November.

Bibliography 207

Kibert, C. J., & Chini, A. (2000). Deconstruction as an essential component of sustainable construction. In Proceedings of the second Southern African conference on sustainable development in the built environment, Pretoria (pp. 1-5).

Kleemann, F., Lederer, J., Aschenbrenner, P., Rechberger, H., & Fellner, J. (2014). A

method for determining buildings’ material composition prior to demolition. Building Research & Information, 44(1), 51-62. doi:10.1080/09613218.2014.979029

Kleemann, F., Lederer, J., Rechberger, H., & Fellner, J. (2017). GIS‐based analysis of

Vienna's material stock in buildings. Journal of Industrial Ecology, 21(2), 368-380.

Kofoworola, O. F., & Gheewala, S. H. (2009). Estimation of construction waste

generation and management in Thailand. Waste management, 29(2), 731-738.

Kontos, T. D., Komilis, D. P., & Halvadakis, C. P. (2005). Siting MSW landfills with a

spatial multiple criteria analysis methodology. Waste management, 25(8), 818-832.

Kourmpanis, B., Papadopoulos, A., Moustakas, K., Kourmoussis, F., Stylianou, M., &

Loizidou, M. (2008). An integrated approach for the management of demolition waste in Cyprus. Waste Management & Research, 26(6), 573-581.

Kourmpanis, B., Papadopoulos, A., Moustakas, K., Stylianou, M., Haralambous, K., &

Loizidou, M. (2008). Preliminary study for the management of construction and demolition waste. Waste Management & Research, 26(3), 267-275.

Kwong, M. H. (2003). Sustainable development in civil engineering—The Hong Kong

experience. In Proc., 2nd Int. Conf. on Construction in the 21st Century (CITC-II) Sustainability and Innovation in Management and Technology (pp. 15-19): Hong Kong Polytechnic Univ.

Lam, P. T., Chan, E. H., Poon, C., Chau, C., & Chun, K. (2010). Factors affecting the

implementation of green specifications in construction. Journal of environmental management, 91(3), 654-661.

Lee, G. K., & Chan, E. H. (2008a). The analytic hierarchy process (AHP) approach for

assessment of urban renewal proposals. Social Indicators Research, 89(1), 155-168.

208 Bibliography

Lee, G. K., & Chan, E. H. (2008b). Factors affecting urban renewal in high-density city: Case study of Hong Kong. Journal of Urban Planning and Development, 134(3), 140-148.

Lee, S. L. (1996). Urban conservation policy and the preservation of historical and

cultural heritage: The case of Singapore. Cities, 13(6), 399-409.

Leigh, N. G., & Patterson, L. M. (2006). Deconstructing to redevelop: A sustainable

alternative to mechanical demolition: The economics of density development finance and pro formas. Journal of the American Planning Association, 72(2), 217-225. doi:10.1080/01944360608976740

Li, H., Chen, Z., Yong, L., & Kong, S. C. (2005). Application of integrated GPS and

GIS technology for reducing construction waste and improving construction efficiency. Automation in Construction, 14(3), 323-331.

Li, J., Ding, Z., Mi, X., & Wang, J. (2013). A model for estimating construction waste

generation index for building project in China. Resources, Conservation and Recycling, 74, 20-26.

Li, S.-M., & Song, Y.-l. (2009). Redevelopment, displacement, housing conditions, and

residential satisfaction: a study of Shanghai. Environment and Planning A, 41(5), 1090-1108.

Liu, C., Pun, S.-K., & Langston, C. (2005a). A preliminary study on building

demolition engineering and management. World Transactions on Engineering and Technology Education, 4(2), 201.

Liu, C., Pun, S., & Langston, C. (2005b). A preliminary study on building demolition

engineering and management. World Transactions on engineering and technology education, 4(2), 201.

Lombardi, D. R., Porter, L., Barber, A., & Rogers, C. D. (2011). Conceptualising

sustainability in UK urban regeneration: A discursive formation. Urban Studies, 48(2), 273-296.

Love, P. E., & Smith, J. (2003). Benchmarking, benchaction, and benchlearning: rework

mitigation in projects. Journal of Management in Engineering, 19(4), 147-159.

Lu, M., Lau, S.-C., & Poon, C.-S. (2009). Simulation approach to evaluating cost

efficiency of selective demolition practices: Case of Hong Kong’s Kai Tak airport demolition. Journal of Construction Engineering and Management, 135(6), 448-457.

Bibliography 209

Lu, W. (2014). Estimating the Amount of Building-Related Construction and

Demolition Waste in China. In Proceedings of the 18th International Symposium on Advancement of Construction Management and Real Estate (pp. 539-548): Springer.

Lu, W., & Yuan, H. (2010). Exploring critical success factors for waste management in

construction projects of China. Resources, conservation and recycling, 55(2), 201-208.

Lu, W., & Yuan, H. (2011). A framework for understanding waste management studies

in construction. Waste Management, 31(2011), 1252-1260. doi:10.1016/j.wasman.2011.01.018

Lu, W., Yuan, H., Li, J., Hao, J. J., Mi, X., & Ding, Z. (2011). An empirical

investigation of construction and demolition waste generation rates in Shenzhen city, South China. Waste management, 31(4), 680-687.

Mália, M., de Brito, J., Pinheiro, M. D., & Bravo, M. (2013). Construction and

demolition waste indicators. Waste Management & Research, 31(3), 241-255. doi:10.1177/0734242X12471707

Manowong, E. (2012). Investigating factors influencing construction waste management

efforts in developing countries: an experience from Thailand. Waste Management & Research, 30(1), 56-71.

Mark, S., Philip, L., & Adrian, T. (Singer-songwriters). (2009). Research methods for

business students. On: Prentice Hall.

Marrero, M., Solis-Guzman, J., Molero-Alonso, B., Osuna-Rodriguez, M., & Ramirez-

de-Arellano, A. (2011). Demolition waste management in Spanish legislation. The Open Construction and Building Technology Journal, 5(Supl 2 M7), 162-173.

Marzouk, M., & Azab, S. (2014). Environmental and economic impact assessment of

construction and demolition waste disposal using system dynamics. Resources, Conservation and Recycling, 82, 41-49.

Mayer, I. S., van Bueren, E. M., Bots, P. W., van der Voort, H., & Seijdel, R. (2005).

Collaborative decisionmaking for sustainable urban renewal projects: a simulation–gaming approach. Environment and Planning B: planning and design, 32(3), 403-423.

210 Bibliography

Mcdonald, B., & Smithers, M. (1998). Implementing a waste management plan during the construction phase of a project: a case study. Construction Management & Economics, 16(1), 71-78. doi:10.1080/014461998372600

McMurray, A. (2004). A commonsense approach: Cengage Learning Australia.

Miller, J. M. (1959). New Life for Cities Around the World: International Handbook on

Urban Renewal: Books International.

Mintzberg, H., & Waters, J. A. (1985). Of strategies, deliberate and emergent. Strategic

management journal, 6(3), 257-272.

Morris, T. (2006). Social work research methods: four alternative paradigms: Sage.

Morrissey, A. J., & Browne, J. (2004). Waste management models and their application

to sustainable waste management. Waste management, 24(3), 297-308.

Mui, D. H.-F., & Sankaran, S. (2004). An effective project management-based

application model for sustainable urban renewal in Hong Kong. In: Project Management Institute.

Mulder, E., de Jong, T. P., & Feenstra, L. (2007). Closed Cycle Construction: An

integrated process for the separation and reuse of C&D waste. Waste Management, 27(10), 1408-1415.

Munoth, N., Jain, R., Raheja, G., & Brar, T. (2013). Issues of Sustainable

Redevelopment of City Core: A Study of Developed and Developing Countries. Journal of The Institution of Engineers (India): Series A, 94(2), 117-122.

Najm, M. A., & El-Fadel, M. (2004). Computer-based interface for an integrated solid

waste management optimization model. Environmental Modelling & Software, 19(2004), 1151-1164. doi:10.1016/j.envsoft.2003.12.005

Nelson, K. P. (1988). Gentrification and distressed cities: an assessment of trends in

intrametropolitan migration. Madison.

Neuman, L. W. (2000). Social research methods: Qualitative and quantitative

approaches (4th ed.). Boston: Allyn and Bacon.

Ng, I. (1998). Urban redevelopment in Hong Kong: The partnership experience.

International Journal of Public Sector Management, 11(5), 414-420.

Bibliography 211

Ng, M. K., Cook, A., & Chui, E. W. (2001). The road not travelled: A sustainable urban

regeneration strategy for Hong Kong. Planning Practice and Research, 16(2), 171-183.

Nguyen, M. (2011). Status of construction waste management in Vietnam. Retrieved

from http://www.xaydungbenvung.com/2014/06/thuc-trang-chat-thai-ran-xay-dung-o.html

Nguyen, M. (2015). Status of construction waste management in Vietnam. Retrieved

from http://www.xaydungbenvung.com/2014/06/thuc-trang-chat-thai-ran-xay-dung-o.html

Nisbet, M., Venta, G., & Foo, S. (2012). Demolition and deconstruction: review of the

current status of reuse and recycling of building materials. AWMA (Air Waste Manag. Assoc.

Omann, I., & Spangenberg, J. H. (2002). Assessing social sustainability. In Biennial

Conference of the International Society for Ecological Economics (Vol. 7).

Ortiz, O., Castells, F., & Sonnemann, G. (2009). Sustainability in the construction

industry: A review of recent developments based on LCA. Construction and Building Materials, 23(1), 28-39.

Osmani, M., Glass, J., & Price, A. D. (2008). Architects’ perspectives on construction

waste reduction by design. Waste Management, 28(7), 1147-1158.

Pallant, J. (Singer-songwriter). (2010). SPSS survival manual: A step by step guide to

data analysis using SPSS . Maidenhead. On: Open University Press/McGraw-Hill.

Papadakis, V. M., Lioukas, S., & Chambers, D. (1998). Strategic decision-making

processes: the role of management and context. Strategic management journal, 19(2), 115-147.

Patton, M. Q. (2002). Qualitative interviewing. Qualitative research and evaluation

methods, 3, 344-347.

Peng, C.-L., Scorpio, D. E., & Kibert, C. J. (1997). Strategies for successful

construction and demolition waste recycling operations. Construction Management & Economics, 15(1), 49-58. doi:10.1080/014461997373105

212 Bibliography

Petersen, M. (2004). Construction Demolition Waste. Vol. 2. J. J. R. Mukesh C. Limbachiya (Ed.) Strategic construction and demolition waste management tool for sustainable urban renewal (pp. 303).

Poon, C., Ann, T., & Ng, L. (2001). On-site sorting of construction and demolition

waste in Hong Kong. Resources, conservation and recycling, 32(2001), 157-172.

Poon, C. S. (1997). Management and recycling of demolition waste in Hong Kong.

Waste management & research, 15, 561-572. doi:10.1080/0144619042000213283

Poon, C. S., Yu, A. T. W., See, S. C., & Cheung, E. (2004). Minimizing demolition

wastes in Hong Kong public housing projects. Construction Management and Economics, 22(8), 799-805.

Power, A. (2008). Does demolition or refurbishment of old and inefficient homes help

to increase our environmental, social and economic viability? Energy Policy, 36(2008), 4487-4501. doi:10.1016/j.enpol.2008.09.022

Qualharini, E. L., & Flemming, L. (2009). Rehabilitation and sustainability of buildings

in Rio de Janeiro. Journal of Building Appraisal, 5(2), 123-131. doi:10.1057/jba.2009.25

Rao, A., Jha, K. N., & Misra, S. (2007). Use of aggregates from recycled construction

and demolition waste in concrete. Resources, conservation and Recycling, 50(1), 71-81.

Rao, C., & Zhang, Q. (2015). Construction Waste Management in Urban Renewal.

International Symposium on Social Science, 2015, 17-20.

Ravetz, J. (2000). Integrated assessment for sustainability appraisal in cities and

regions. Environmental impact assessment review, 20(1), 31-64.

Rodríguez, G., Alegre, F. J., & Martínez, G. (2007). The contribution of environmental

management systems to the management of construction and demolition waste: The case of the Autonomous Community of Madrid (Spain). Resources, conservation and recycling, 50(3), 334-349.

Rogers, G., & Bouey, E. (1996). Collecting your data. Qualitative research for social

workers: Phases, steps, and tasks, 4, 50-87.

Bibliography 213

Rotmans, J., van Asselt, M., & Vellinga, P. (2000). An integrated planning tool for sustainable cities. Environmental impact assessment review, 20(3), 265-276.

Roussat, N., Dujet, C., & Mehu, J. (2009a). Choosing a sustainable demolition waste

management strategy using multicriteria decision analysis. Waste management, 29(2009), 12-20. doi:10.1016/j.wasman.2008.04.010

Roussat, N., Dujet, C., & Mehu, J. (2009b). Choosing a sustainable demolition waste

management strategy using multicriteria decision analysis. Waste management, 29, 12-20. doi:10.1016/j.wasman.2008.04.010

Roussat, N., Méhu, J., Abdelghafour, M., & Brula, P. (2008). Leaching behaviour of

hazardous demolition waste. Waste Management, 28, 2032-2040. doi:10.1016/j.wasman.2007.10.019

Şener, Ş., Şener, E., Nas, B., & Karagüzel, R. (2010). Combining AHP with GIS for

landfill site selection: a case study in the Lake Beyşehir catchment area (Konya, Turkey). Waste management, 30(11), 2037-2046.

Seo, S., & Hwang, Y. (1999). An estimation of construction and demolition debris in

Seoul, Korea: waste amount, type, and estimating model. Journal of the Air & Waste Management Association, 49(8), 980-985. doi:10.1080/10473289.1999.10463863

Shen, L. Y., Li Hao, J., Tam, V. W. Y., & Yao, H. (2007). A checklist for assessing

sustainability performance of construction projects. Journal of civil engineering and management, 13(4), 273-281.

Sohn, S.-K. (2003). Changes in the Residential Features of Seoul in the 20th Century.

Seoul, 20th Century: Growth and Change of the Last, 100.

Somasundaram, S., Jeon, T.-W., Kang, Y.-Y., Kim, W.-I., Jeong, S.-K., Kim, Y.-J., . . .

Shin, S. K. (2015). Characterization of wastes from construction and demolition sector. Environmental monitoring and assessment, 187(1), 1-14. doi:10.1007/s10661-014-4200-0

Spangenberg, H. (2004). Sustainability beyond environmentalism: the missing

dimensions. GoSDWorking, Paper No. 2

Sproull, N. L. (2002). Handbook of research methods: A guide for practitioners and

students in the social sciences: Scarecrow press.

214 Bibliography

Steinberg, F. (1996). Conservation and rehabilitation of urban heritage in developing countries. Habitat International, 20(3), 463-475.

Sumathi, V., Natesan, U., & Sarkar, C. (2008). GIS-based approach for optimized siting

of municipal solid waste landfill. Waste management, 28(11), 2146-2160. doi:10.1016/j.wasman.2007.09.032

Tam, V. W. (2008). On the effectiveness in implementing a waste-management-plan

method in construction. Waste management, 28(6), 1072-1080.

Tam, V. W., & Tam, C. M. (2008). Waste reduction through incentives: a case study.

Building Research & Information, 36(1), 37-43.

Tanikawa, H., & Hashimoto, S. (2009). Urban stock over time: spatial material stock

analysis using 4d-GIS. Building Research & Information, 37(5-6), 483-502.

Thomas, J. M., & Hwang, H.-Y. (2003). Social Equity in Redevelopment and Housing

United States and Korea. Journal of Planning Education and Research, 23(1), 8-23.

Turok, I., & Mykhnenko, V. (2007). The trajectories of European cities, 1960–2005.

Cities, 24(3), 165-182.

USEPA. (2009). Estimating 2003 building-related construction and demolition materials

amounts. Retrieved December 13, 2017, from US. Environmental Protection Agency

Uzun, C. N. (2005). Residential transformation of squatter settlements: Urban

redevelopment projects in Ankara. Journal of Housing and the Built Environment (20(2), 183-199. doi:DOI: 10.1007/s10901-005-9002-9

van Bueren, E., & ten Heuvelhof, E. (2005). Improving governance arrangements in

support of sustainable cities. Environment and planning B: Planning and Design, 32(1), 47-66.

van Dijk, S., Tenpierik, M., & van den Dobbelsteen, A. (2014). Continuing the

building's cycles: A literature review and analysis of current systems theories in comparison with the theory of Cradle to Cradle. Resources, Conservation and Recycling, 82, 21-34.

Bibliography 215

Van Selm, M., & Jankowski, N. W. (2006). Conducting online surveys. Quality & Quantity, 40(3), 435-456.

Vego, G., Kučar-Dragičević, S., & Koprivanac, N. (2008). Application of multi-criteria

decision-making on strategic municipal solid waste management in Dalmatia, Croatia. Waste management, 28(11), 2192-2201.

Vietnamnet. (2016). The list of 42 high risk old buildings in Hanoi. Retrieved from

http://vietnamnet.vn/vn/bat-dong-san/cong-bo-danh-sach-42-chung-cu-cu-nguy-hiem-sap-do-o-ha-noi-290358.html

Walker, A. (2015). Project management in construction: John Wiley & Sons.

Wang, J.-Y., Kang, X.-P., & Wing-Yan Tam, V. (2008). An investigation of

construction wastes: an empirical study in Shenzhen. Journal of Engineering, Design and Technology, 6(3), 227-236.

Wang, J., & Yuan, H. (2006). Integrated analysis of the current situation of construction

industry in Chinese eight major provinces and cities. Construction economy, 9, 5-8.

Wang, J., & Yuan, H. (2008). On-site construction waste management model based on

system dynamics. Science & Technology Progress and Policy, 25(10), 74-78.

Wang, J., & Yuan, H. (2011). Factors affecting contractors’ risk attitudes in

construction projects: Case study from China. International Journal of Project Management, 29(2), 209-219.

Wang, J. Y., Touran, A., Christoforou, C., & Fadlalla, H. (2004). A systems analysis

tool for construction and demolition wastes management. Waste management, 24(10), 989-997. doi:10.1016/j.wasman.2004.07.010

WCED, W. C. o. E. a. D. (1987). Our Common Future. Retrieved from

Williams, K., & Dair, C. (2007). What is stopping sustainable building in England?

Barriers experienced by stakeholders in delivering sustainable developments. Sustainable development, 15(3), 135-147.

Wilson, D. C., Velis, C. A., & Rodic, L. (2013). Integrated sustainable waste

management in developing countries. In Proceedings of the Institution of Civil Engineers: Waste and Resource Management (Vol. 166, pp. 52-68): Thomas Telford.

216 Bibliography

Wong, E. O., & Yip, R. C. (2004). Promoting sustainable construction waste

management in Hong Kong. Construction Management and Economics, 22(6), 563-566. doi:10.1080/0144619042000226270

Wu, F., & He, S. (2005). Changes in traditional urban areas and impacts of urban

redevelopment: a case study of three neighbourhoods in Nanjing, China. Tijdschrift voor economische en sociale geografie, 96(1), 75-95.

Wu, H., Wang, J., Duan, H., Ouyang, L., Huang, W., & Zuo, J. (2016). An innovative

approach to managing demolition waste via GIS (geographic information system): a case study in Shenzhen city, China. Journal of Cleaner Production, 112, 494-503.

Wu, Z., & Ann, T. (2014). Evaluating the effectiveness of construction and demolition

waste management strategies. In Proceedings of the 18th International Symposium on Advancement of Construction Management and Real Estate (pp. 531-538): Springer.

Wu, Z., Ann, T., Shen, L., & Liu, G. (2014). Quantifying construction and demolition

waste: An analytical review. Waste Management, 34(9), 1683-1692.

Wyatt, D. P., & Gilleard, J. (1994). Deconstruction: an environmental response for

construction sustainability. In Sustainable Construction, Proceedings of the 1st International Conference of CIB TG16, Tampa, Fla (pp. 6-9).

Yan, H., Shen, Q., Fan, L. C., Wang, Y., & Zhang, L. (2010). Greenhouse gas emissions

in building construction: A case study of One Peking in Hong Kong. Building and Environment, 45(4), 949-955.

Yau, Y., & Ling Chan, H. (2008). To rehabilitate or redevelop? A study of the decision

criteria for urban regeneration projects. Journal of Place Management and Development, 1(3), 272-291. doi:10.1108/17538330810911262

Yeh, A. G.-O. (1990). Public and private partnership in urban redevelopment in Hong

Kong. Third World Planning Review, 12(4), 361-383.

Yeheyis, M., Hewage, K., Alam, M. S., Eskicioglu, C., & Sadiq, R. (2013). An

overview of construction and demolition waste management in Canada: a lifecycle analysis approach to sustainability. Clean Technologies and Environmental Policy, 15(1), 81-91.

Bibliography 217

Yeoh, B. S., & Huang, S. (1996). The conservation-redevelopment dilemma in Singapore: the case of the Kampong Glam historic district. Cities, 13(6), 411-422.

Yeung, A. (2008). Construction and demolition materials management in Hong Kong.

In Proceedings of the Institution of Civil Engineers: Municipal Engineer (Vol. 161, pp. 43-49): Thomas Telford (ICE Publishing). The Journal's web site is located at http://www. municipalengineer. com.

Yeung, J. F., Chan, A. P., Chan, D. W., & Li, L. K. (2007). Development of a

partnering performance index (PPI) for construction projects in Hong Kong: a Delphi study. Construction Management and Economics, 25(12), 1219-1237.

Yin, R. K. (2013). Case study research: Design and methods: Sage publications.

Yost, P. A., & Halstead, J. M. (1996). A methodology for quantifying the volume of

construction waste. Waste management & research, 14(5), 453-461.

Yuan, H. (2011). A dynamic model for assessing the effectiveness of construction and

demolition waste management. The Hong Kong Polytechnic University. Retrieved from http://hdl.handle.net/10397/4917

Yuan, H. (2013). A SWOT analysis of successful construction waste management.

Journal of Cleaner Production, 39, 1-8.

Yuan, H., & Shen, L. (2011). Trend of the research on construction and demolition

waste management. Waste management, 31(4), 670-679. doi:10.1016/j.wasman.2010.10.030

Yuan, H., Shen, L., & Wang, J. (2011). Major obstacles to improving the performance

of waste management in China's construction industry. Facilities, 29(5/6), 224-242. doi:10.1108/02632771111120538

Zhang, X., & Li, Y. (2012). Multi-Attribute Decision Making in Choosing Suitable

Construction Waste Management Methods. In Construction Research Congress 2012: Construction Challenges in a Flat World, Proceedings of the 2012 Construction Research Congress.

Zhao, W., Leeftink, R., & Rotter, V. (2010). Evaluation of the economic feasibility for

the recycling of construction and demolition waste in China—The case of Chongqing. Resources, Conservation and Recycling, 54(6), 377-389.

218 Bibliography

Zheng, H. W., Shen, G. Q., & Wang, H. (2014). A review of recent studies on sustainable urban renewal. Habitat International, 41, 272-279.

Zielenbach, S. (2000). Art of Revitalization: Taylor & Francis.

Zimmermann, M., Althaus, H.-J., & Haas, A. (2005). Benchmarks for sustainable

construction: A contribution to develop a standard. Energy and Buildings, 37(11), 1147-1157.

Zuckerman, M. (1991). Psychobiology of personality: Combrige University Press.

Appendices 219

Appendices

APPENDIX A. QUESTIONNAIRE SURVEY

Appendix A1: A sample of questionnaire (in English)

Survey on factors affecting demolition waste management in urban redevelopment

projects in Vietnam

This questionnaire is part of a PhD research that aims to improve the decision-making processes of demolition waste management from urban redevelopment in Vietnam. The objective of the questionnaire is to identify factors affecting the demolition waste management.

Your response is kept strictly confidential.

Note: Urban redevelopment in this research is defined as demolition of aging buildings and constructions of new buildings on the same site, including residential and commercial buildings.

SECTION 1. RESPONDENT INFORMATION

1. Please indicate your current position?

Academic

Planner

Consultant

Engineer

Policy maker

Other

2. What is the business nature of your organization?

Government agency

Local authority

Academic institution

Construction contractor

Waste management contractor

Other

3. How long have you been involved in practice/research in waste management?

0-5 years

5-10 years

10-15 years

15-20 years

Over 20 years

4. What is your organization’s level of involvement in demolition waste management?

Never

Rarely

Sometime

Often

220 Appendices

Always

5. What is your role in demolition waste management?

Director/Manager

Decision maker

Site engineer

Waste transporter

Other

SECTION 2. GENERAL INFORMATION

6. Please indicate the location of your last complete urban redevelopment project?

Hanoi

Hai Phong

Ho Chi Minh City

Other

7. Which of the following describes accurately your last complete urban redevelopment project scale?

Within a building

Multi-building

Multi-project

Other

8. In your professional capacity, which stakeholders do you need to work with?

Government agency

Local authority

Planner

Technical contractor

Construction contractor

Other

9. Making plans before demolition stage is important to urban redevelopment demolition waste management?

Strong disagree

Disagree

Neither agree nor disagree

Agree

Strongly agree

10. Which aspects do you think the most important in urban redevelopment demolition waste management?

Cost

Environment

Time

Safety

Policy

Other

Appendices 221

SECTION 3. FACTORS AFFECTING THE DECISION-MAKING PROCESS OF URBAN REDEVELOPMENT DEMOLITION WASTE MANAGEMENT

The following 5 categories contain the most significant identified factors to the decision-making process of demolition waste management in urban redevelopment projects. With your experience, please indicate the appropriate rating level in each that describes the significance of these factors.

11. Technical factors

Not at all important

(1)

Low important

(2)

Neither important

nor unimportant

(3)

Very important

(4)

Extremely important

(5)

Sufficient equipment for demolition project

Training the human resources in demolition techniques

Skilled personnel are available for conducting demolition project

Choosing demolition method (reduction of demolition time, cost and waste)

The use of selective demolition method (on-site sorting, separate waste for reuse and recycling)

Determining the procedures of demolition waste management

On-site sorting/separating of demolition waste

Estimating the amount of demolition waste

The use of BIM-based model in demolition waste management

The use of GIS-based model in demolition waste management

Planning the area for landfills

Planning the area for sorting platform

Planning storage space for recyclable materials

Managing time of the duration of demolition

Identifying ricks associate with building’s demolition

Life cycle assessment

222 Appendices

12. Environmental factors


(1)

Low important

(2)

Neither important nor unimportant

(3)

Very important

(4)

Extremely important

(5)

Understanding environmental issues of demolition waste generation

The willingness of demolition waste management by stakeholders




Promotion of 3R in demolition waste management (reduction, reuse and recycling of demolition waste)

The use of recycled materials

Understanding of hazardous demolition waste

Disposal control (fee, landfill sites)

Identifying rate of recovery

Balancing of greenhouse gases

13. Economic factors


(1)

Low important

(2)


(3)

Very important

(4)

Extremely important

(5)

Estimating the cost of demolition

Estimating the cost of waste transport

Estimating the cost of waste treatment

Cost- effective demolition plans

Developing of recycling market

Reducing cost of demolition waste transportation

Saving the amount of energy use (fuels, electricity and others)

Developing an appropriate cost for waste disposal

Appendices 223

14. Social factors

Not at allimportant

(1)

Low important

(2)


(3)

Very important

(4)

Extremely important

(5)

The role of community in demolition waste management

Community’s supportive actions before demolition stage

Community’s monitoring of environmental conditions during demolition stage

Effective feedback by community

Reduction of risks, accidences for workers on demolition site

Reduction of community disturbance during demolition stage (e.g. demolition noise, dust and other pollutions)

Preservation of natural resources, cultural and heritage


Job creation due to demolition waste management

15. Institutional factors

Not at allimportant

(1)

Low important

(2)


(3)

Very important

(4)

Extremely important

(5)

The roles of key stakeholders in monitoring and feedback

Understanding of responsibilities by all stakeholders

Understanding of demolition waste management procedures

Effective feedback by stakeholders

Demolition project control meeting

Providing guidelines of demolition waste management plan

Regular information update

Involvement of key stakeholders in early stage

224 Appendices

Accomplishing government’s policy and strategy on demolition waste management

16. The following statements are related to an impact of the significant factors listed in the previous section to improve decision-making process for demolition waste management. With your experience, please indicate the level of agreement with the statements by circling the appropriate scale.

Strongly agree

Disagree Neither agree nor disagree

Agree Strongly agree

Environment degradation should be paid more attention

Maximise profit from demolition waste is my concern

Develop a planning tool (ICT-based solutions)

Develop a forum of communication among stakeholders

Manage demolition waste in multi- buildings/projects

17. Please state any other relevant points which have not been mentioned anywhere in this questionnaire.

SECTION 4. FURTHER INFORMATION

18. Please indicate whether the researchers can contact you for a follow-up interview?

Yes

No

Please enter your most convenient contact information such as name, company, email address and phone

number (personal information will remain confidential)

Thank you very much for contributing your valuable time in completing this questionnaire! Should you have any enquiries about this survey or the scope of my research, please do not hesitate to contact me as shown below:

Diep Thi Bui

Phone: +61 452256311

Email: [email protected]

-END-

Appendices 225

Appendix A2: A sample of questionnaire (in Vietnamese)

Nghiên cứu các yếu tố ảnh hưởng đến công tác quản lý chất thải phá dỡ của các dự án cải tạo chung cư cũ ở Việt nam

Bảng khảo sát này phục vụ luận án tiến sỹ của nghiên cứu sinh Bùi Thi Diệp.

Nghiên cứu này nhằm mục tiêu cải thiện quá trình ra quyết định trong việc quản lý chất thải phá dỡ có nguồn gốc từ các dự án cải tạo chung cư cũ ở Việt nam. Bảng các các câu hỏi được thực

hiện nhằm xác định rõ các yếu tố làm ảnh hưởng đến công tác quản lý chất thải phá dỡ.

Bảng câu hỏi không yêu cầu nêu tên và thông tin cá nhân của anh/chị.

Xin cảm ơn anh/chị đã tham gia đóng góp cho nghiên cứu. Mọi câu trả lời của quý vị được bảo đảm giữ bí mật một cách tuyệt đối.

Lưu ý: Dự án cải tạo chung cư cũ trong nghiên cứu này được hiểu là quá trình phá dỡ các các tòa nhà chung cư cũ và xây dựng mới trên cùng vị trí.

PHẦN 1. THÔNG TIN NGHỀ NGHIỆP

1. Xin vui lòng cho biết chức danh của anh/chị?

Nghiên cứu viên

Chuyên viên lập kế hoạch

Tư vấn môi trường

Kỹ sư xây dựng

Chuyên viên xây dựng chính sách

Khác

2. Cơ quan của anh/chị là:

Quản lý nhà nước

Chính quyền địa phương

Đơn vị nghiên cứu

Nhà thầu xây dựng

Nhà thầu quản lý chất thải

Khác

3. Kinh nghiệm của anh/chị đã tham gia thực hiện/nghiên cứu trong lĩnh vực quản lý chất thải phá dỡ?

0-5 năm

5-10 năm

10-15 năm

15-20 năm

Trên 20 năm

4. Cơ quan của anh/chị tham gia quản lý chất thải phá dỡ ở mức độ nào?

Chưa bao giờ

226 Appendices

Hiếm khi

Thỉnh thoảng

Thường thường

Luôn luôn

5. Vai trò của anh/chị trong dự án quản lý chất thải phá dỡ:

Quản lý dự án

Giám sát dự án, xây dựng quy định

Kỹ sư công trường

Vận chuyển chất thải phá dỡ

Khác

PHẦN 2. THÔNG TIN VỀ DỰ ÁN CẢI TẠO CHUNG CƯ CŨ

6. Xin vui lòng cho biết địa danh mà anh/chị đã tham gia thực hiện dự án quản lý chất thải phá dỡ?

Hà Nội

Hải Phòng

Thành phố Hồ Chính Minh

Khác

7. Quy mô dự án cải tạo chung cư cũ mà anh/chị đã tham gia thực hiện?

Một tòa nhà

Nhiều tòa nhà

Nhiều dự án

Khác

8. Khi thực hiện dự án, anh/chị cần làm việc với những đối tác nào?

Cơ quan quản lý nhà nước

Chính quyền địa phương

Cơ quan quy hoạch xây dựng

Cơ quan kỹ thuật

Nhà thầu xây dựng

Khác

9. Việc lập kế hoạch trước khi phá dỡ có quan trọng đối với quản ý chất thải phá dỡ?

Hoàn toàn không đồng ý

Không đồng ý

Bình thường

Đồng ý

Hoàn toàn đồng ý

10. Theo anh/chị yếu tố nào là có ảnh hưởng nhất đối với quản lý chất thảo phá dỡ ở chung cư cũ?

Chi phí thực hiện dự án

Bảo vệ môi trường

Thời gian thực hiện dự án

An toàn lao động

Appendices 227

Chính sách quản lý chất thải

Khác

PHẦN 3. NHỮNG YẾU TỐ ẢNH HƯỞNG ĐẾN CÔNG TÁC QUẢN LÝ CHẤT THẢI PHÁ DỠ

Nghiên cứu bước đầu xác định các yếu tố ảnh hưởng đến công tác quản lý chất thải phá dỡ và chia theo 5 nhóm chính, đó là nhóm các yếu tố kỹ thuật, môi trường, kinh tế, xã hội và thể chế. Theo kinh nghiệm của anh/chị, xin hãy đánh giá mức độ quan trọng của các yếu tố đối với công tác quản lý chất thải phá dỡ theo thang điểm từ 1 đến 5 (từ hoàn toàn không quan trọng đến cực kỳ quan trọng).

11. Các yếu tố kỹ thuật

Hoàn toàn không quan

trọng (1)

Không quan trọng (2)

Bình thường

(3)

Rất quan trọng (4)

Cực kỳ quan trọng (5)

Trang bị đầy đủ phương tiện phá dỡ

Đào tạo nguồn nhân lực về kỹ thuật phá quản lý chất thải

Kỹ năng của người thực hiện công tác phá dỡ

Lựa chọn phương pháp phá dỡ (giảm thiểu thời gian, giá thành, khối lượng chất thải)

Áp dụng phương pháp phá dỡ chọn lọc (phân loại chất thải tại công trình, phân loại chấtthải cho tái sử dụng và tái chế)

Xác định quy trình quản lý chất thải phá dỡ

Phân loại chất thải tại công trình

Ước lượng khối lượng chất thải phá dỡ

Áp dụng mô trình quản lý thông tin xây dựng (BIM) trong quản lý chất thải phá dỡ

Áp dụng Hệ thống thông tin địa lý (GIS) trong quản lý chất thải phá dỡ

Hoạch định bãi chứa chất thải phá dỡ

Hoạch định khu vực phân loại chất thải phá dỡ

Hoạch định khu vực chứa chất thải có thể tái chế

Giám sát thời gian thực hiện phá dỡ

228 Appendices

Xác định các rủi ro trong quá trình phá dỡ

Đánh giá vòng đời chất thải phá dỡ

12. Các yếu tố môi trường

Hoàn toàn

không quantrọng (1)


Bình thường

(3)



Xác định các vấn đề môi trường do chất thải phá dỡ gây ra

Các bên liên quan sẵn sàng tham gia quản lý chất thải phá dỡ

Đào tạo nguồn nhân lực cho quản lý tổng hợp chất thải

Khảo sát thành phần chất thải phá dỡ trước khi thực hiện phá dỡ

Đánh giá tác động môi trường của công tác phá dỡ

Áp dụng chiến lược 3R trong quản lý chất thải phá dỡ (giảm thiểu, tái sử dụng và tái chế)

Chính sách khuyến khích tái chế chất thải phá dỡ

Xác định chất thải phá dỡ có tinh độc hại

Kiểm soát việc chôn lấp chất thải phá dỡ (lệphí, bãi chứa)

Xác định tỷ lệ tái sử dụng và tái chế chất thải phá dỡ

Biện pháp giảm phát thải khí nhà kính do chất thải phá dỡ

13. Các yếu tố kinh tế

Hoàn toàn

không quantrọng (1)


Bình thường

(3)



Khái toán chi phí phá dỡ

Khái toán chi phí vận chuyển chất thải

Khái toán chi phí xử lý chất thải

Đánh giá hiệu quả kinh tế của các phương án phá dỡ

Phát triển thị trường vật liệu tái chế

Appendices 229

Giảm chi phí vận chuyển chất thải phá dỡ

Tiết kiệm sử dụng năng lượng (xăng dầu, điện)

Xây dựng biểu giá chôn lấp chất thải phù hợp

230 Appendices

14. Các yếu tố xã hội


trọng (1)


Bình thường

(3)



Vai trò của cộng đồng trong việc quản lý chất thải phá dỡ

Các hoạt động hỗ trợ của cộng đồng trước khi thực hiện phá dỡ (đánh giá, phân loại chất thải, tuyên truyền về 3R)

Sự tham gia giám sát môi trường của cộng đồng trong quá trình phá dỡ

Lấy ý kiến phản hồi của cộng đồng về quá trình phá dỡ

Giảm thiểu rủi ro cho người lao động khi thực hiệnphá dỡ

Giảm thiểu tác động môi trường cho cộng đồngtrong quá trình phá dỡ (tiếng ồn, bụi, ô nhiễm khác)

Bảo vệ tài nguyên thiên nhiên và di sản văn hóa trong quá trình phá dỡ và xử lý chất thải

Nâng cao ý thức cộng đồng về quản lý tổng hợp chất thải và cải tạo chung cư cũ bền vững

Quản lý chất thải phá dỡ tạo cơ hội việc làm cho xã hội

15. Các yếu tố thể chế


trọng (1)


Bình thường

(3)



Vai trò của các bên tham gia trong công tác giám sát và đánh giá quản lý chất thải phá dỡ

Phân công nhiệm vụ cụ thể cho các bên tham gia

Các bên tham gia được thông tin đầy đủ về quy trình quản lý chất thải phá dỡ

Vai trò quan trọng của công tác tổng kết, đánh giá của các bên tham gia

Họp các bên liên quan về đánh giá, theo dõi dự án phá dỡ và công tác quản lý chất thải

Ban hành văn bản hướng dẫn thực hiện quản lý chất thải phá dỡ

Thường xuyên cập nhật thông tin về chất thải trong quá trình phá dỡ

Sự tham gia của các bên liên quan từ giai đoạnchuẩn bị thực hiện dự án phá dỡ

Hoàn thiện chính sách và chiến lược đối với công tác quản lý chất thải phá dỡ

Appendices 231

16. Với kinh nghiệm của bản thân, xin anh/chị cho biết mức độ đồng ý của mình về các yếu tố cần được xem xét trong quá trình ra quyết định quản lý chất thải phá dỡ?

Hoàn toàn không đồng ý

Không đồng ý

Bình thường

Đồng ý Hoàn toàn đồng ý

Cần phải chú trọng hơn nữa đến các vấn đề môi trường (bảo vệ tài nguyên, cảnh quan, ô nhiễm môi trường, chôn lấp hợp vệ sinh)

Tăng giá trị kinh tế từ chất thảiphá dỡ đến mức tối đa (Tái chế, tái sử dụng)

Áp dụng công nghệ thông tin hỗtrợ quá trình ra quyết định quản lý chất thải phá dỡ (BIM, GIS hoặc phần mềm khác)

Thiết lập diễn đàn thông tincho các bên tham gia có thể dễ dàng chia sẻ và cập nhật thông tin về quản lý chất thải phá dỡ

Quản lý chất thải phá dỡ ở quy mô lớn gồm nhiều toà nhà hoặc dự án phá dỡ

17. Ngoài các yếu tố ảnh hưởng đã nêu, xin anh/chị vui lòng nêu và nhận xét về vấn đề nổi bật khác ảnh hưởng đến công tác quản lý chất thải phá dỡ của các dự án cải tạo chung cư cũ

PHẦN 4. THÔNG TIN KHÁC

18. Anh/chị có sẵn sàng tham gia cuộc phỏng vấn trong thời gian tới (sau khi nghiên cứu có kết quả của vòng trả lời câu khỏi khảo sát này)?

Có

Không

Nếu có, anh/chị hãy cho biết thông tin liên hệ thuận tiện nhất như họ tên, công ty, địa chỉ email, số điện thoại (thông tin cá nhân luôn được bảo mật)

Rất cám ơn anh/chị đã dành thời gian để trả lời bộ câu hỏi này. Nếu anh/chị muốn nhận được bản tóm tắt kết quả nghiên cứu của khảo sát này, xin liên lạc theo địa chỉ dưới đây. Kết quả sẽ được gửi sau khi nghiên cứu được hoàn thành và được phép công bố.

Thông tin liên lạc của nghiên cứu sinh: Bùi Thi Diệp ĐT: +61 452256311


-HẾT-

232 Appendices

Appendix A3: Invitation Letter - Questionnaire Survey Invitation to a survey on:

Critical factors of improving demolition waste management for Vietnamese

urbane redevelopment projects

Dear Sir/madam

My name is Diep Thi Bui from School of Civil Engineering & Built Environment,

Queensland University of Technology (QUT). I am currently undertaking a PhD into the

improvement of decision-making process of demolition waste management for

Vietnamese urban redevelopment.

I’m looking for stakeholders, i.e. experts from construction firms, construction and

demolition waste firms, government agencies, and academic institutions to complete a

25-30 minute online questionnaire. You will be asked about your experience and opinions

regarding factors affecting DW management decision-making in Vietnamese urban

redevelopment projects. Your answers are of importance for the research team to

recognise the critical factors and issues associated with urban redevelopment DW

management.

Please view the attached Participant Information Sheet and Consent Form for further

details on the study.

Should you wish to participate or have any questions, please contact me via email.

Please note that this study has been approved by the QUT Human Research Ethics

Committee (approval number 1600000588).

Best regards

Diep Thi Bui

PhD Candidate Student



Queensland University of Technology (QUT)

Tel: +61 4 5225 6311/+84 9 0345 5101


Appendices 233

APPENDIX B. SURVEY ANALYSIS RESULTS

Appendix B1: Results of normality test

Factors Kolmogorov-Smirnov Shapiro-Wilk

Statistic df Sig. Statistic df Sig.

Sufficient equipment for demolition project

.273 216 .000 .808 216 .000

Training the human resources in demolition techniques

.282 216 .000 .812 216 .000

Skilled personnel are available for conducting demolition project

.325 216 .000 .798 216 .000

Choosing demolition method (reduction of demolition time, cost andwaste)

.342 216 .000 .754 216 .000

The use of selective demolition method (on-site sorting, separate wastefor reuse and recycling)

.319 216 .000 .794 216 .000

Determining the procedures of demolition waste management

.365 216 .000 .684 216 .000

On-site sorting/separating of demolition waste

.360 216 .000 .677 216 .000

Estimating the amount of demolition waste .291 216 .000 .782 216 .000

The use of BIM-based modelr in demolition waste management

.347 216 .000 .750 216 .000

The use of GIS-based model in demolition waste management

.285 216 .000 .824 216 .000

Planning the area for landfills .325 216 .000 .766 216 .000

Planning the area for sorting platform .305 216 .000 .783 216 .000

Planning storage space for recyclable materials

.378 216 .000 .686 216 .000

Managing time of the duration of demolition

.375 216 .000 .726 216 .000

Identifying ricks associate with building’s demolition

.397 216 .000 .702 216 .000

Life cycle assessment .314 216 .000 .801 216 .000

Understanding environmental issues of demolition waste generation

.309 216 .000 .791 216 .000

The willingness of demolition waste management by stakeholders

.284 216 .000 .794 216 .000


.346 216 .000 .750 216 .000


.344 216 .000 .752 216 .000

Environmental Impact Assessment .328 216 .000 .770 216 .000

234 Appendices



Promotion of 3R in demolition waste management (reduction, reuse and recycling of demolition waste)

.306 216 .000 .762 216 .000

The use of recycled materials .339 216 .000 .767 216 .000

Understanding of hazardous demolition waste

.318 216 .000 .791 216 .000

Disposal control (fee, landfill sites) .300 216 .000 .774 216 .000

Identifying rate of waste recovery .338 216 .000 .760 216 .000

Balancing of greenhouse gases .324 216 .000 .763 216 .000

Estimation of demolition cost .323 216 .000 .774 216 .000

Cost estimation of waste transport .297 216 .000 .783 216 .000

Cost estimation of waste treatment .315 216 .000 .776 216 .000

Cost- effective demolition plans .274 216 .000 .770 216 .000

Developing of recycling market .337 216 .000 .756 216 .000

Reducing cost of demolition waste transportation

.288 216 .000 .806 216 .000

Saving the amount of energy use (fuels, electricity and others)

.308 216 .000 .797 216 .000

Developing an appropriate cost for waste disposal

.311 216 .000 .762 216 .000

The role of community in decision making process

.328 216 .000 .765 216 .000

Community’s supportive actions before demolition stage

.284 216 .000 .827 216 .000

Community’s monitoring of environmental conditions during demolition stage

.324 216 .000 .793 216 .000

Effective feedback by community .305 216 .000 .807 216 .000

Reduction of risks, accidences for workers on demolition site

.330 216 .000 .796 216 .000


.232 216 .000 .805 216 .000

Preservation of natural resources, cultural and heritage

.395 216 .000 .673 216 .000


.299 216 .000 .817 216 .000

Job creation due to demolition waste management

.318 216 .000 .752 216 .000

The roles of key stakeholders in monitoring and feedback

.255 216 .000 .784 216 .000

Appendices 235



Understanding of responsibilities by all stakeholders

.281 216 .000 .768 216 .000

Understanding of demolition waste management procedures

.431 216 .000 .635 216 .000

Effective feedback by stakeholders .333 216 .000 .760 216 .000

Demolition project control meeting .316 216 .000 .776 216 .000

Providing guidelines of demolition waste management plan

.369 216 .000 .632 216 .000

Regular information update .334 216 .000 .712 216 .000

Involvement of key stakeholders in early stage

.402 216 .000 .664 216 .000

Accomplishing government’s policy and strategy on demolition waste management

.360 216 .000 .736 216 .000

236 Appendices

Appendix B2: Academics’ ratings of decision-making factors of demolition waste

management

No. Decision-making Factors N Minimum Maximum Mean Std.

Deviation Rank

I. Technical factors 3.951


52 3 5 4.392 .563 2


52 3 5 4.373 .559 3

3 Planning the area for landfills 52 3 5 4.235 .580 9

4 Planning the area for sorting platform 52 3 5 4.176 .706 13

5 Estimating the amount of demolition waste

52 3 5 4.118 .548 19

6 The use of GIS-based model in demolition waste management

52 3 5 4.118 .646 20


52 3 5 4.098 .634 21


52 3 5 3.980 .542 24


52 3 5 3.961 .685 25


52 3 5 3.902 .602 28


52 3 5 3.765 .613 37

12 Identifying ricks associate with building’s demolition

52 3 5 3.745 .555 38

13 The use of BIM-based model in demolition waste management

52 3 5 3.706 .497 40


52 3 5 3.627 .559 41


52 3 5 3.588 .691 43

16 Life cycle assessment 52 2 4 3.431 .533 48

II. Environmental factors 3.970


52 3 5 4.314 .700 5


52 3 5 4.294 .666 6


52 3 5 4.196 .525 11

4 Identifying rate of waste recovery 52 3 5 4.176 .584 14


52 3 5 4.157 .538 16

Appendices 237


Deviation Rank

6 Environmental Impact Assessment 52 3 5 4.137 .657 17


52 3 5 3.922 .589 26

8 The use of recycled materials 52 3 5 3.863 .542 32


52 3 5 3.863 .595 33

10 Disposal control (fee, landfill sites) 52 2 5 3.490 .606 46

11 Balancing of greenhouse gases 52 2 4 3.255 .555 49

III. Economic factors 3.914

1 Cost- effective demolition plans 52 3 5 4.333 .705 4

2 Cost estimation of waste transport 52 3 5 4.137 .687 18

3 Estimation of demolition cost 52 3 5 4.078 .621 22

4 Developing of recycling market 52 3 5 3.922 .621 27


52 3 5 3.902 .602 29

6 Cost estimation of waste treatment 52 3 5 3.765 .703 36


52 3 5 3.725 .563 39


52 2 4 3.451 .636 47

IV. Social factors 3.368


52 3 5 4.255 .518 8

2


52 3 5 4.039 .713 23


52 3 5 3.608 .716 42

4


52 2 5 3.588 .746 44


52 2 4 3.588 .566 45


52 2 5 3.176 .759 50


52 2 4 3.118 .582 51


52 1 4 2.490 .668 52

238 Appendices


Deviation Rank

9 Effective feedback by community 52 1 4 2.451 .636 53

V. Institutional factors 4.076


52 4 5 4.412 .492 1

2 Regular information update 52 3 5 4.294 .604 7


52 3 5 4.235 .644 10


52 3 5 4.196 .687 12


52 3 5 4.176 .473 15

6 Effective feedback by stakeholders 52 3 5 3.902 .533 30


52 3 5 3.882 .582 31


52 3 5 3.804 .486 34

9 Demolition project control meeting 52 3 5 3.784 .571 35

Appendices 239

Appendix B3: Planners’ ratings of decision-making factors of demolition waste

management


Deviation Rank



37 4 5 4.405 .498 3



37 3 5 4.297 .463 8


37 4 5 4.297 .661 9


37 3 5 4.108 .516 15


37 3 5 4.108 .567 17



37 2 5 4.027 .833 23


37 3 5 3.838 .442 26


37 2 5 3.811 .739 28


37 3 5 3.784 .479 31

12 The use of BIM-based modelin demolition waste management

37 3 5 3.622 .545 39


37 2 5 3.486 .692 43


37 2 5 3.432 .603 45



37 2 5 2.973 .763 48



37 3 5 4.270 .450 10


37 4 5 4.270 .608 11


37 3 5 4.216 .630 12




37 3 5 3.973 .552 25


37 2 5 3.757 .548 32


240 Appendices


Deviation Rank


37 2 5 3.622 .639 38









37 3 5 3.757 .683 33



37 2 5 3.514 .692 42


37 2 4 3.243 .548 47



37 3 5 4.162 .553 14


37 3 5 4.108 .737 16


37 2 4 3.649 .538 37


37 3 5 3.541 .558 40

5


37 3 5 3.541 .650 41


37 2 5 2.973 .687 49


37 2 4 2.838 .442 50


37 1 4 2.622 .758 52




37 4 5 4.568 .502 1



37 3 5 4.405 .644 4


37 3 5 4.324 .709 7


37 3 5 4.216 .534 13


Appendices 241


Deviation Rank


37 3 5 4.054 .705 20


37 3 5 3.811 .518 29


242 Appendices

Appendix B4: Consultants’ ratings of decision-making factors of demolition waste

management


Deviation Rank



29 3 5 4.517 .574 1


29 4 5 4.448 .506 2


29 3 5 4.310 .712 7



29 3 5 4.207 .563 11



29 3 5 3.966 .566 19


29 3 5 3.931 .623 21


29 3 5 3.931 .651 23


29 3 5 3.897 .557 25


29 3 5 3.862 .693 26


29 3 5 3.793 .559 32


29 3 5 3.690 .712 40


29 3 5 3.655 .553 41


29 2 5 3.552 .686 44



1 2. The willingness of demolition waste management by stakeholders

29 3 5 4.379 .728 3

2 4. Understanding the uniqueness of demolition waste before demolition stage

29 3 5 4.310 .541 8


29 3 5 4.241 .577 9

Appendices 243


Deviation Rank




29 3 5 3.931 .651 24


29 3 5 3.759 .577 36




29 3 5 3.621 .677 43







29 3 5 3.860 .693 29




29 3 4 3.517 .509 45


29 2 4 3.103 .618 48



29 4 5 4.345 .484 6

2 Reduction of community disturbance during demolition stage (e.g.demolition noise, dust and other pollutions)

29 3 5 3.966 .680 20


29 3 5 3.759 .689 33

4


29 3 5 3.690 .541 39


29 3 5 3.483 .634 46


29 2 4 2.793 .559 50


244 Appendices


Deviation Rank


29 2 4 2.690 .604 52


29 2 4 2.655 .553 53



29 4 5 4.379 .494 4



29 3 5 4.172 .602 12


29 3 5 4.172 .658 14


29 3 5 4.103 .409 17


29 3 5 3.862 .516 28




29 3 5 3.759 .636 34

Appendices 245

Appendix B5: Engineers’ rating of decision-making factors of demolition waste

management


Deviation Rank



57 3 5 4.491 .539 1


57 3 5 4.421 .533 3


57 2 5 4.298 .706 10


57 3 5 4.263 .583 12


57 3 5 4.263 .642 13


57 3 5 4.228 .598 14




57 3 5 3.947 .692 27


57 3 5 3.912 .714 30


57 2 5 3.895 .489 34


57 3 5 3.872 .588 35


57 2 5 3.860 .611 37


57 2 5 3.772 .535 38


57 3 4 3.491 .504 46




57 3 5 4.211 .559 15


57 3 5 4.193 .549 16


57 2 5 4.018 .582 22


246 Appendices


Deviation Rank



57 3 5 3.912 .606 31


57 3 5 3.772 .682 39



57 2 5 3.754 .635 41









57 2 5 3.965 .706 26



57 3 5 3.737 .669 42


57 2 4 3.281 .620 48



57 4 5 4.351 .481 7


57 3 5 4.158 .774 17


57 2 5 4.105 .724 19


57 3 5 3.702 .706 43

5


57 2 5 3.632 .698 45


57 2 4 3.053 .666 49


57 2 4 2.982 .582 50

Appendices 247


Deviation Rank


57 1 4 2.667 .607 52





57 3 5 4.404 .704 4


57 4 5 4.368 .487 6


57 3 5 4.316 .686 9


57 3 5 4.263 .483 11


57 3 5 3.982 .551 24



57 3 5 3.912 .544 32


248 Appendices

Appendix B6: Policy Makers’ rating of decision-making factors of demolition waste

management


Deviation Rank



43 4 5 4.333 .471 6


43 4 5 4.310 .462 8



43 3 5 4.126 .586 17


43 3 5 4.119 .543 18


43 3 5 4.071 .402 22


43 2 5 3.929 .632 24



43 3 5 3.881 .391 27


43 3 5 3.738 .491 32


43 3 5 3.714 .502 36


43 3 5 3.714 .665 37


43 2 5 3.524 .587 42


43 3 4 3.405 .491 45



43 2 4 3.214 .465 47



43 3 5 4.381 .615 3


43 3 5 4.310 .597 7


Appendices 249


Deviation Rank


43 3 5 4.119 .662 19



43 3 5 4.095 .750 21



43 3 5 3.667 .678 38


43 1 5 3.647 .777 40










43 3 5 3.738 .657 34


43 2 5 3.476 .698 44


43 2 4 3.190 .587 48



43 4 5 4.429 .495 2


43 3 5 4.238 .717 11


43 3 5 3.762 .526 31


43 3 5 3.667 .713 39

250 Appendices


Deviation Rank

5


43 2 5 3.524 .763 43


43 2 4 2.881 .697 50


43 1 4 2.690 .672 51


43 1 4 2.643 .610 52




43 4 5 4.524 .499 1



43 3 5 4.381 .653 5


43 3 5 4.262 .657 10


43 3 5 4.190 .449 14


43 3 5 3.905 .366 25


43 3 5 3.857 .559 29



Appendices 251

APPENDIX C. INVITATION LETTER – INTERVIEW

Invitation to an interview on:

CRITICAL FACTORS OF IMPROVING DEMOLITION WASTE MANAGEMENT

FOR VIETNAMESE URBANE REDEVELOPMENT PROJECTS

Dear Sir/madam

Thanks again for agreeing to take part in the study. I am writing to confirm our meeting on date,

time.

To quickly recap, I am currently undertaking a PhD study in the School of Civil Engineering and

Built Environment, Science and Engineering Faculty at Queensland University of Technology

(QUT). I am doing a study into the improvement of decision-making process of demolition waste

management for Vietnam urban redevelopment at a large scale.

The interview questions will be sent for your reference before the interview takes place.

The main items to be discussed are:

1. The significant influence of critical factors of urban redevelopment DW management in

Vietnam.

2. Comment on related policy and strategy of urban redevelopment DW management in

Vietnam.

3. Comment on the challenges and opportunities that might be faced by critical factors in the

context of Vietnam.

4. Provide your opinion about the action plans for improving DW management in Vietnamese

urban redevelopment projects.

Please note that this study has been approved by the QUT Human Research Ethics Committee

(approval number 1600000588). Please kindly see the attached sheet (Participant information for

QUT research project) for more information about my research.

The confidentiality of every participant in this study is of the utmost importance. Your identity

will not be disclosed and data summited will not be identified by the responses.

Should you wish to find out more about the research or have any questions, please contact me via

email.

Best regards

Diep Thi Bui

PhD Candidate Student

252 Appendices



Queensland University of Technology (QUT)

Tel: +61 4 5225 6311/+84 9 0345 5101


Appendices 253

APPENDIX D. DATA COLLECTION AND ANALYSIS FOR CASE STUDY

Appendix D1: Estimation of demolition waste for each urban redevelopment project in Ba Dinh district

No Project Building name Block

symbol

Block Length

(m)

Block width (m)

Storey numbers

Total block height (m)

1 Giang Vo Building D GV_D1 71.3 11.87 5 15.0





5 Ngoc Khanh I Building A NK_A1 79.2 10.87 5 15.0

6 Ngoc Khanh I Building A NK_A2 79.2 10.87 5 15.0

7 Ngoc Khanh I Building B NK_B 79.2 10.77 5 15.0

8 Ngoc Khanh II Building D NK_D1 31.8 12.87 3 8.4

9 Ngoc Khanh II Building D NK_D2 31.8 12.87 3 8.4

10 Ngoc Khanh II Building D NK_D3A 28.8 12.87 3 8.4

11 Ngoc Khanh II Building D NK_D3B 27.0 12.87 3 8.4

12 Thanh Cong Building A TC_A1 103.5 12.77 5 15.0






18 Thanh Cong Building A TC_A6A 51.8 12.77 5 15.0

19 Thanh Cong Building B TC_B1 169.7 11.77 5 15.0


21 Thanh Cong Building B TC_B2A 106.9 12.77 4 12.0






27 Thanh Cong Building D TC_D1 69.6 9.57 5 15.0





32 Thanh Cong Building D TC_D4_1 30.3 8.77 5 15.0

33 Thanh Cong Building D TC_D4_2 33.7 8.77 5 15.0




254 Appendices

No Storey height

(m)

unit numbers in each floor

Stair numbers of each floor

Width of each

stair (m)

unit height in actual use (m)

unit length

actual use (m)

unit width in actual

use (m)

Total unit area in

actual use (m2)

1 3.0 16 2 3.4 2.8 9.2 3.8 35.0

2 3.0 16 2 3.4 2.8 9.2 3.8 35.0

2 3.0 16 2 3.4 2.8 9.2 3.8 35.0

3 3.0 16 2 3.4 2.8 9.2 3.8 35.0

4 3.0 16 2 3.4 2.8 9.2 3.8 35.0

5 3.0 12 2 3.4 2.8 8 5.8 46.4

6 3.0 12 2 3.4 2.8 8 5.8 46.4

7 3.0 12 2 3.4 2.8 8 5.8 46.4 8 2.8 8 1 2.8 2.8 10 3.4 34.0

9 2.8 8 1 2.8 2.8 10 3.4 34.0 10 2.8 6 1 2.8 2.8 10 4.1 41.0

11 2.8 6 1 2.8 2.8 10 3.8 38.0

12 3.0 24 2 3.4 2.8 10 3.8 38.0

13 3.0 24 2 3.4 2.8 10 3.8 38.0

14 3.0 24 2 3.4 2.8 10 3.8 38.0

15 3.0 24 2 3.4 2.8 10 3.8 38.0

16 3.0 24 2 3.4 2.8 10 3.8 38.0

17 3.0 12 1 3.4 2.8 10 3.8 38.0

18 3.0 12 1 3.4 2.8 10 3.8 38.0

19 3.0 36 3 3.4 2.8 9 4.2 37.8

20 3.0 8 1 3.4 2.8 10 3.8 38.0

21 3.0 24 3 3.4 2.8 10 3.8 38.0

22 3.0 8 1 3.4 2.8 10 3.8 38.0

23 3.0 8 1 3.4 2.8 10 3.8 38.0

24 3.0 24 3 3.4 2.8 10 3.8 38.0

25 3.0 8 1 3.4 2.8 10 3.8 38.0

26 3.0 8 1 3.4 2.8 10 3.8 38.0

27 3.0 12 2 3.4 2.8 6.8 5 34.0

28 3.0 6 1 3.4 2.8 6.8 5 34.0

29 3.0 6 1 3.4 2.8 6.8 5 34.0

30 3.0 6 1 3.4 2.8 6.8 5 34.0

31 3.0 12 2 3.4 2.8 6.8 5 34.0

32 3.0 4 1 3.4 2.8 6 6.5 39.0

33 3.0 4 2 3.4 2.8 6 6.5 39.0

34 3.0 12 2 3.4 2.8 6.8 5 34.0

35 3.0 12 2 3.4 2.8 6.8 5 34.0

36 3.0 6 1 3.4 2.8 6.8 5 34.0

Appendices 255

No Room number in each

unit

Width of bed

room 1 (m)

Length of bed room 1

(m)

Total bed room 1

area (m2)

Total wall area of bed

room 1 (m2)

Width of bed room

2 (m)

Length of bed room

2 (m)

Total bed room 2

area (m2)

1 4 3.7 3.8 15.37 42.08 2 4 8.95

2 4 3.7 3.8 15.37 42.08 2 4 8.95

2 4 3.7 3.8 15.37 42.08 2 4 8.95

3 4 3.7 3.8 15.37 42.08 2 4 8.95

4 4 3.7 3.8 15.37 42.08 2 4 8.95

5 4 2.8 5.8 17.58 49.88 2.8 5.2 15.83

6 4 2.8 5.8 17.58 49.88 3.8 5.2 21.26

7 4 2.8 5.8 17.58 49.88 3.8 5.2 21.26

8 3 2.8 5 15.25 43.26 2.8 3.6 11.16

9 3 2.8 5 15.25 43.26 2.8 3.6 11.16

10 3 3.2 5.8 19.99 57.32 2.8 3.6 11.16

11 3 3 5.8 18.78 53.94 2.8 3.6 11.16

12 4 2 6 13.18 38.35 2 4 8.95

13 4 2 6 13.18 38.35 2 4 8.95

14 4 2 6 13.18 38.35 2 4 8.95

15 4 2 6 13.18 38.35 2 4 8.95

16 4 2 6 13.18 38.35 2 4 8.95

17 4 2 6 13.18 38.35 2 4 8.95

18 4 2 6 13.18 38.35 2 4 8.95

19 4 2.6 5 14.20 40.25 2.6 4 11.48

20 4 2.6 5 14.20 40.25 2.6 4 11.48

21 4 2.6 5 14.20 40.25 2.6 4 11.48

22 4 2.6 5 14.20 40.25 2.6 4 11.48

23 4 2.6 5 14.20 40.25 2.6 4 11.48

24 4 2.6 5 14.20 40.25 2.6 4 11.48

25 4 2.6 5 14.20 40.25 2.6 4 11.48

26 4 2.6 5 14.20 40.25 2.6 4 11.48

27 4 3.5 3.2 12.40 33.47 3.5 3.6 13.85

28 4 3.2 3.5 12.36 33.67 3.5 3.6 13.85

29 4 3.2 3.5 12.36 33.67 3.5 3.6 13.85

30 4 3.5 3.2 12.40 33.47 3.5 3.6 13.85

31 4 3.5 3.2 12.40 33.47 3.5 3.6 13.85

32 4 3.5 4 15.29 42.34 2.5 4.8 13.15

33 4 3.5 4 15.29 42.34 3.5 3.6 13.85

34 4 3.2 3.5 12.36 33.67 3.5 3.6 13.85

35 4 3.2 3.5 12.36 33.67 3.5 3.6 13.85

36 4 3.2 3.5 12.36 33.67 3.5 3.6 13.85

256 Appendices

No Total wall area of bed room 2 (m2)

Width of

dining room (m)

Length of dining room (m)

Total dining

room area (m2)

Total wall area of dining

room (m2)

Width of bath

room & WC (m)

Length of bath room & WC (m)

Total bath room & WC area

(m2)

1 25.96 1.8 5.5 10.97 34.58 1.5 2 3.60

2 25.96 1.8 5.5 10.97 34.58 1.5 2 3.60

2 25.96 1.8 5.5 10.97 34.58 1.5 2 3.60

3 25.96 1.8 5.5 10.97 34.58 1.5 2 3.60

4 25.96 1.8 5.5 10.97 34.58 1.5 2 3.60

5 46.09 3 3.7 12.24 36.39 1.5 2.2 3.92

6 61.29 3 3.7 12.24 36.39 1.5 2.2 3.92

7 61.29 3 3.7 12.24 36.39 1.5 2.2 3.92

8 32.00 1.8 2.2 4.65 13.86 1.5 1.5 2.79

9 32.00 1.8 2.2 4.65 13.86 1.5 1.5 2.79

10 32.00 1.8 2.2 4.65 13.86 1.5 2 3.60

11 32.00 1.8 2.2 4.65 13.86 1.5 2 3.60

12 26.26 1.8 7 13.85 44.07 1.8 3 6.19

13 26.26 1.8 7 13.85 44.07 1.8 3 6.19

14 26.26 1.8 7 13.85 44.07 1.8 3 6.19

15 26.26 1.8 7 13.85 44.07 1.8 3 6.19

16 26.26 1.8 7 13.85 44.07 1.8 3 6.19

17 26.26 1.8 7 13.85 44.07 1.8 3 6.19

18 26.26 1.8 7 13.85 44.07 1.8 3 6.19

19 33.36 1.6 6 10.68 34.25 1.6 3 5.54

20 33.36 1.6 6 10.68 34.25 1.6 3 5.54

21 33.36 1.6 6 10.68 34.25 1.6 3 5.54

22 33.36 1.6 6 10.68 34.25 1.6 3 5.54

23 33.36 1.6 6 10.68 34.25 1.6 3 5.54

24 33.36 1.6 6 10.68 34.25 1.6 3 5.54

25 33.36 1.6 6 10.68 34.25 1.6 3 5.54

26 33.36 1.6 6 10.68 34.25 1.6 3 5.54

27 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

28 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

29 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

30 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

31 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

32 38.81 2 4.5 10.00 30.90 1.5 2 3.60

33 39.59 2 4.5 10.00 30.90 1.5 2 3.60

34 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

35 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

36 39.59 1.5 3.8 6.51 20.44 1.5 3 5.22

Appendices 257

No Total wall area of bath & WC (m2)

Corridor width per unit (m)

Wall height of corridor

barrier per unit (m)

Total wall area of corridor

barrier per unit (m2)

Balcony numbers in unit

Balcony width in unit (m)

Balcony length in unit (m)

1 10.74 1.4 1.2 4.8 1 0.8 3.8

2 10.74 1.4 1.2 4.8 1 0.8 3.8

2 10.74 1.4 1.2 4.8 1 0.8 3.8

3 10.74 1.4 1.2 4.8 1 0.8 3.8

4 10.74 1.4 1.2 4.8 1 0.8 3.8

5 11.54 1.6 1.2 7.2 1 0.8 5.8

6 11.54 1.6 1.2 7.2 1 0.8 5.8

7 11.54 1.6 1.3 7.8 1 0.8 5.8

8 8.05 1.6 1.3 4.7 1 0.8 3.4

9 8.05 1.6 1.3 4.7 1 0.8 3.4

10 10.80 1.6 1.3 5.6 1 0.8 3.4

11 10.80 1.6 1.3 5.2 1 0.8 3.4

12 19.24 1.5 1.3 5.2 1 0.8 3.8

13 19.24 1.5 1.3 5.2 1 0.8 3.8

14 19.24 1.5 1.3 5.2 1 0.8 3.8

15 19.24 1.5 1.3 5.2 1 0.8 3.8

16 19.24 1.5 1.3 5.2 1 0.8 3.8

17 19.24 1.5 1.3 5.2 1 0.8 3.8

18 19.24 1.5 1.3 5.2 1 0.8 3.8

19 17.43 1.5 1.3 5.8 1 0.8 4.2

20 17.43 1.5 1.3 5.2 1 0.8 3.8

21 17.43 1.5 1.3 5.2 1 0.8 3.8

22 17.43 1.5 1.3 5.2 1 0.8 3.8

23 17.43 1.5 1.3 5.2 1 0.8 3.8

24 17.43 1.5 1.3 5.2 1 0.8 3.8

25 17.43 1.5 1.3 5.2 1 0.8 3.8

26 17.43 1.5 1.3 5.2 1 0.8 3.8

27 16.53 1.5 1.3 6.8 1 0.8 5

28 16.53 1.5 1.3 6.8 1 0.8 5

29 16.53 1.5 1.3 6.8 1 0.8 5

30 16.53 1.5 1.3 6.8 1 0.8 5

31 16.53 1.5 1.3 6.8 1 0.8 5

32 11.04 1.5 1.3 8.7 1 0.8 6.5

33 11.04 1.5 1.3 8.7 1 0.8 6.5

34 16.53 1.5 1.3 6.8 1 0.8 5

35 16.53 1.5 1.3 6.8 1 0.8 5

36 16.53 1.5 1.3 6.8 1 0.8 5

258 Appendices

No Wall height of

balcony of unit (m)

Total wall area of balcony in

each unit (m2)

Door numbers in each unit

Door height in each unit

(m)

Door width in each unit

(m)

Each door area of each

unit (m2)

Door material

1 1 4.0 5 2.1 0.8 1.68 Iron

2 1 4.0 5 2.1 0.8 1.68 Iron

2 1 4.0 5 2.1 0.8 1.68 Iron

3 1 4.0 5 2.1 0.8 1.68 Iron

4 1 4.0 5 2.1 0.8 1.68 Iron

5 1 6.0 5 2.1 0.8 1.68 Iron

6 1 6.0 5 2.1 0.8 1.68 Iron

7 1 6.0 5 2.1 0.8 1.68 Iron

8 1 3.6 5 1.9 0.8 1.52 Iron

9 1 3.6 5 1.9 0.8 1.52 Iron

10 1 4.3 5 1.9 0.8 1.52 Iron

11 1 4.0 5 1.9 0.8 1.52 Iron

12 1 4.0 5 2.1 0.8 1.68 Iron

13 1 4.0 5 2.1 0.8 1.68 Iron

14 1 4.0 5 2.1 0.8 1.68 Iron

15 1 4.0 5 2.1 0.8 1.68 Iron

16 1 4.0 5 2.1 0.8 1.68 Iron

17 1 4.0 5 2.1 0.8 1.68 Iron

18 1 4.0 5 2.1 0.8 1.68 Iron

19 1 4.4 5 2.1 0.8 1.68 Iron

20 1 4.0 5 2.1 0.8 1.68 Iron

21 1 4.0 5 2.1 0.8 1.68 Iron

22 1 4.0 5 2.1 0.8 1.68 Iron

23 1 4.0 5 2.1 0.8 1.68 Iron

24 1 4.0 5 2.1 0.8 1.68 Iron

25 1 4.0 5 2.1 0.8 1.68 Iron

26 1 4.0 5 2.1 0.8 1.68 Iron

27 1 5.2 5 2.1 0.8 1.68 Iron

28 1 5.2 5 2.1 0.8 1.68 Iron

29 1 5.2 5 2.1 0.8 1.68 Iron

30 1 5.2 5 2.1 0.8 1.68 Iron

31 1 5.2 5 2.1 0.8 1.68 Iron

32 1 6.7 5 2.1 0.8 1.68 Iron

33 1 6.7 5 2.1 0.8 1.68 Iron

34 1 5.2 5 2.1 0.8 1.68 Iron

35 1 5.2 5 2.1 0.8 1.68 Iron

36 1 5.2 5 2.1 0.8 1.68 Iron

Appendices 259

No Specific

weight of ion

(kg/m3)

Total weight of door (kg)

Window number in each unit

Window height in each unit

(m)

Window width in each unit

(m)

Each window area in

each unit (m2)

Window material

Total weight of window

(kg)

1 770 77.616 2 1.5 1 1.5 Wood 69.3 2 770 77.616 2 1.5 1 1.5 Wood 69.3

2 770 77.616 2 1.5 1 1.5 Wood 69.3

3 770 77.616 2 1.5 1 1.5 Wood 69.3

4 770 77.616 2 1.5 1 1.5 Wood 69.3

5 770 77.616 2 1.5 1.2 1.8 Iron 83.16

6 770 77.616 2 1.5 1.2 1.8 Iron 83.16

7 770 77.616 2 1.5 1.2 1.8 Iron 83.16

8 770 70.224 2 1.2 1.2 1.44 Iron 66.528

9 770 70.224 2 1.2 1.2 1.44 Iron 66.528

10 770 70.224 2 1.2 1.2 1.44 Iron 66.528

11 770 70.224 2 1.2 1.2 1.44 Iron 66.528

12 770 77.616 2 1.2 1 1.2 Wood 55.44

13 770 77.616 2 1.2 1 1.2 Wood 55.44

14 770 77.616 2 1.2 1 1.2 Wood 55.44

15 770 77.616 2 1.2 1 1.2 Wood 55.44

16 770 77.616 2 1.2 1 1.2 Wood 55.44

17 770 77.616 2 1.2 1 1.2 Wood 55.44

18 770 77.616 2 1.2 1 1.2 Wood 55.44

19 770 77.616 2 1.2 1 1.2 Wood 55.44

20 770 77.616 2 1.2 1 1.2 Wood 55.44

21 770 77.616 2 1.2 1 1.2 Wood 55.44

22 770 77.616 2 1.2 1 1.2 Wood 55.44

23 770 77.616 2 1.2 1 1.2 Wood 55.44

24 770 77.616 2 1.2 1 1.2 Wood 55.44

25 770 77.616 2 1.2 1 1.2 Wood 55.44

26 770 77.616 2 1.2 1 1.2 Wood 55.44

27 770 77.616 2 1.2 1 1.2 Wood 55.44

28 770 77.616 2 1.2 1 1.2 Wood 55.44

29 770 77.616 2 1.2 1 1.2 Wood 55.44

30 770 77.616 2 1.2 1 1.2 Wood 55.44

31 770 77.616 2 1.2 1 1.2 Wood 55.44

32 770 77.616 2 1.2 1 1.2 Wood 55.44

33 770 77.616 2 1.2 1 1.2 Wood 55.44

34 770 77.616 2 1.2 1 1.2 Wood 55.44

35 770 77.616 2 1.2 1 1.2 Wood 55.44

36 770 77.616 2 1.2 1 1.2 Wood 55.44

260 Appendices

No Total wall area for each

unit (m2)

Number of brick for wall in each unit

Specific weight of

brick (kg/brick)

Total weight of brick for wall in each

unit (kg)

Mortar weight for wall in each

unit (liter)

Mortar cover weight for wall in each unit (liter)

1 122.2 19,799.9 1.6 31,679.8 5,500.0 2,077.8

2 122.2 19,799.9 1.6 31,679.8 5,500.0 2,077.8

2 122.2 19,799.9 1.6 31,679.8 5,500.0 2,077.8

3 122.2 19,799.9 1.6 31,679.8 5,500.0 2,077.8

4 122.2 19,799.9 1.6 31,679.8 5,500.0 2,077.8

5 157.2 25,460.3 1.6 40,736.5 7,072.3 2,671.8

6 172.4 27,923.4 1.6 44,677.4 7,756.5 2,930.2

7 172.9 28,016.9 1.6 44,827.0 7,782.5 2,940.0

8 105.5 17,094.2 1.6 27,350.8 4,748.4 1,793.8

9 105.5 17,094.2 1.6 27,350.8 4,748.4 1,793.8

10 123.9 20,076.7 1.6 32,122.6 5,576.8 2,106.8

11 119.9 19,417.8 1.6 31,068.5 5,393.8 2,037.7

12 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

13 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

14 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

15 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

16 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

17 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

18 137.2 22,224.5 1.6 35,559.2 6,173.5 2,332.2

19 135.5 21,949.0 1.6 35,118.4 6,096.9 2,303.3

20 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

21 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

22 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

23 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

24 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

25 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

26 134.6 21,799.9 1.6 34,879.9 6,055.5 2,287.6

27 122.1 19,772.2 1.6 31,635.6 5,492.3 2,074.9

28 122.2 19,803.5 1.6 31,685.6 5,501.0 2,078.1

29 122.2 19,803.5 1.6 31,685.6 5,501.0 2,078.1

30 122.1 19,772.2 1.6 31,635.6 5,492.3 2,074.9

31 122.1 19,772.2 1.6 31,635.6 5,492.3 2,074.9

32 138.6 22,448.1 1.6 35,916.9 6,235.6 2,355.7

33 139.3 22,574.2 1.6 36,118.7 6,270.6 2,368.9

34 122.2 19,803.5 1.6 31,685.6 5,501.0 2,078.1

35 122.2 19,803.5 1.6 31,685.6 5,501.0 2,078.1

36 122.2 19,803.5 1.6 31,685.6 5,501.0 2,078.1

Appendices 261

No Specific weight of mortar (kg/liter)

Total weight of mortar cover

weight for wall in each unit

(kg)

Total weigth of wall for each

unit (kg)

Total ceiling area of each

unit (m2)

Ceiling volume of each unit

(m3)

Cement weight for ceiling in each unit (kg)

1 1.6 12,124.4 43,804.1 35.0 7.0 2,587.0

2 1.6 12,124.4 43,804.1 35.0 7.0 2,587.0

2 1.6 12,124.4 43,804.1 35.0 7.0 2,587.0

3 1.6 12,124.4 43,804.1 35.0 7.0 2,587.0

4 1.6 12,124.4 43,804.1 35.0 7.0 2,587.0

5 1.6 15,590.5 56,327.1 46.4 9.3 3,433.6

6 1.6 17,098.8 61,776.2 46.4 9.3 3,433.6

7 1.6 17,156.0 61,983.0 46.4 9.3 3,433.6

8 1.6 10,467.6 37,818.4 34.0 6.8 2,516.0

9 1.6 10,467.6 37,818.4 34.0 6.8 2,516.0

10 1.6 12,293.9 44,416.5 41.0 8.2 3,034.0

11 1.6 11,890.4 42,959.0 38.0 7.6 2,812.0

12 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

13 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

14 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

15 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

16 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

17 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

18 1.6 13,609.1 49,168.3 38.0 7.6 2,812.0

19 1.6 13,440.4 48,558.7 37.8 7.6 2,797.2

20 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

21 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

22 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

23 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

24 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

25 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

26 1.6 13,349.1 48,229.0 38.0 7.6 2,812.0

27 1.6 12,107.4 43,743.0 34.0 6.8 2,516.0

28 1.6 12,126.6 43,812.2 34.0 6.8 2,516.0

29 1.6 12,126.6 43,812.2 34.0 6.8 2,516.0

30 1.6 12,107.4 43,743.0 34.0 6.8 2,516.0

31 1.6 12,107.4 43,743.0 34.0 6.8 2,516.0

32 1.6 13,746.0 49,662.9 39.0 7.8 2,886.0

33 1.6 13,823.2 49,941.9 39.0 7.8 2,886.0

34 1.6 12,126.6 43,812.2 34.0 6.8 2,516.0

35 1.6 12,126.6 43,812.2 34.0 6.8 2,516.0

36 1.6 12,126.6 43,812.2 34.0 6.8 2,516.0

Appendices i

No Yellow sand weight for

ceiling in each unit (m3)

Specific weight of yellow sand

(kg/m3)

Total weight of yellow sand for ceiling in

each unit (kg)

Macadam weight for

ceiling in each unit (m3)

Specific weight of macadam

(kg/m3)

Total weight of macadam for ceiling in each

unit (kg)

1 3.6 1,450.0 5,272.0 5.0 1,500.0 7,425.5

2 3.6 1,450.0 5,272.0 5.0 1,500.0 7,425.5

2 3.6 1,450.0 5,272.0 5.0 1,500.0 7,425.5

3 3.6 1,450.0 5,272.0 5.0 1,500.0 7,425.5

4 3.6 1,450.0 5,272.0 5.0 1,500.0 7,425.5

5 4.8 1,450.0 6,997.1 6.6 1,500.0 9,855.4

6 4.8 1,450.0 6,997.1 6.6 1,500.0 9,855.4

7 4.8 1,450.0 6,997.1 6.6 1,500.0 9,855.4

8 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

9 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

10 4.3 1,450.0 6,182.8 5.8 1,500.0 8,708.4

11 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

12 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

13 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

14 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

15 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

16 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

17 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

18 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

19 3.9 1,450.0 5,700.2 5.4 1,500.0 8,028.7

20 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

21 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

22 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

23 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

24 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

25 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

26 4.0 1,450.0 5,730.4 5.4 1,500.0 8,071.2

27 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

28 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

29 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

30 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

31 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

32 4.1 1,450.0 5,881.2 5.5 1,500.0 8,283.6

33 4.1 1,450.0 5,881.2 5.5 1,500.0 8,283.6

34 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

35 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

36 3.5 1,450.0 5,127.2 4.8 1,500.0 7,221.6

ii Appendices

No Steel germ weight for ceiling in each unit

(kg)

Mortar cover

weight for ceiling in each unit

Toral weight of mortar

cover for ceiling in

Total weight of ceiling for each unit

(kg)

Enameled tile

number for floor in each

Specific weight of enameled

tile for floor in

Total weight of enameled

tile for floor in

Mortar cover

weight for floor in

each unit

Total weight of mortar

cover for floor in

1 2,223.5 559.4 895.0 18,402.9 1,538 0.25 385 541.9 867.0

2 2,223.5 559.4 895.0 18,402.9 1,538 0.25 385 541.9 867.0

2 2,223.5 559.4 895.0 18,402.9 1,538 0.25 385 541.9 867.0

3 2,223.5 559.4 895.0 18,402.9 1,538 0.25 385 541.9 867.0

4 2,223.5 559.4 895.0 18,402.9 1,538 0.25 385 541.9 867.0

5 2,951.0 556.8 890.9 24,128.0 2,042 0.25 510 719.2 1,150.7

6 2,951.0 556.8 890.9 24,128.0 2,042 0.25 510 719.2 1,150.7

7 2,951.0 556.8 890.9 24,128.0 2,042 0.25 510 719.2 1,150.7

8 2,162.4 272.0 435.2 17,462.4 1,496 0.25 374 527.0 843.2

9 2,162.4 272.0 435.2 17,462.4 1,496 0.25 374 527.0 843.2

10 2,607.6 246.0 393.6 20,926.4 1,804 0.25 451 635.5 942.4

11 2,416.8 228.0 364.8 19,395.2 1,672 0.25 418 589.0 942.4

12 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

13 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

14 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

15 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

16 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

17 2,416.8 456.0 729.6 19,760.0 1,672 0.25 418 589.0 942.4

18 2,416.8 456.0 729.6 19,760.0 1,672 0.25 418 589.0 942.4

19 2,404.1 304.0 2,177.3 21,107.5 1,663 0.25 416 585.9 937.4

20 2,416.8 304.0 486.4 19,516.8 1,672 0.25 418 589.0 942.4

21 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

22 2,416.8 304.0 486.4 19,516.8 1,672 0.25 418 589.0 942.4

23 2,416.8 304.0 486.4 19,516.8 1,672 0.25 418 589.0 942.4

24 2,416.8 912.0 1,459.2 20,489.6 1,672 0.25 418 589.0 942.4

25 2,416.8 304.0 486.4 19,516.8 1,672 0.25 418 589.0 942.4

26 2,416.8 304.0 486.4 19,516.8 1,672 0.25 418 589.0 942.4

27 2,162.4 408.0 652.8 17,680.0 1,496 0.25 374 527.0 843.2

28 2,162.4 204.0 326.4 17,353.6 1,496 0.25 374 527.0 843.2

29 2,162.4 204.0 326.4 17,353.6 1,496 0.25 374 527.0 843.2

30 2,162.4 204.0 326.4 17,353.6 1,496 0.25 374 527.0 843.2

31 2,162.4 408.0 652.8 17,680.0 1,496 0.25 374 527.0 843.2

32 2,480.4 156.0 249.6 19,780.8 1,716 0.25 429 604.5 967.2

33 2,480.4 156.0 249.6 19,780.8 1,716 0.25 429 604.5 967.2

34 2,162.4 408.0 652.8 17,680.0 1,496 0.25 374 527.0 843.2

35 2,162.4 408.0 652.8 17,680.0 1,496 0.25 374 527.0 843.2

36 2,162.4 204.0 326.4 17,353.6 1,496 0.25 374 527.0 843.2

Appendices iii

No White cement

weight for floor in

each unit

Total weight of floor for each unit

(kg)

Number of pillars

Area of each pillar

(m2)

Height of each pillar

(m)

Metal weight for each pillar

(kg)

Cement weight for each pillar

(kg)

Sand weight for each pillar

(m3)

1 8.390 1,259.96 6 0.09 2.8 80.14 .24 0.13

2 8.390 1,259.96 6 0.09 2.8 80.14 93.24 0.13

2 8.390 1,259.96 6 0.09 2.8 80.14 93.24 0.13

3 8.390 1,259.96 6 0.09 2.8 80.14 93.24 0.13

4 8.390 1,259.96 6 0.09 2.8 80.14 93.24 0.13

5 11.136 1,672.26 6 0.09 2.8 80.14 93.24 0.13

6 11.136 1,672.26 6 0.09 2.8 80.14 93. 9324 0.13

7 11.136 1,672.26 6 0.09 2.8 80.14 93.24 0.13

8 8.160 1,225.36 6 0.09 2.8 80.14 93.24 0.13

9 8.160 1,225.36 6 0.09 2.8 80.14 93.24 0.13

10 9.840 1,477.64 6 0.09 2.8 80.14 93.24 0.13

11 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

12 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

13 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

14 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

15 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

16 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

17 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

18 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

19 9.072 1,362.31 6 0.09 2.8 80.14 93.24 0.13

20 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

21 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

22 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

23 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

24 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

25 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

26 9.120 1,369.52 6 0.09 2.8 80.14 93.24 0.13

27 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

28 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

29 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

30 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

31 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

32 9.360 1,405.56 4.5 0.09 2.8 80.14 93.24 0.13

33 9.360 1,405.56 4.5 0.09 2.8 80.14 93.24 0.13

34 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

35 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

36 8.160 1,225.36 4.5 0.09 2.8 80.14 93.24 0.13

iv Appendices

No Total weight

of sand for each pillar

(kg)

Macadam weight for each pillar

(m3)

Total weight of macadam for

each pillar (kg)

Total weight for pillar of

each department

Total weigth for each unit (ton)

Total weight for each building (ton)

1 190.008 0.20 294.84 3949.34 67.56 5405.06

2 190.008 0.20 294.84 3949.34 67.56 5405.06

2 190.008 0.20 294.84 3949.34 67.56 5405.06

3 190.008 0.20 294.84 3949.34 67.56 5405.06

4 190.008 0.20 294.84 3949.34 67.56 5405.06

5 190.008 0.20 294.84 3949.34 86.24 5174.25

6 190.008 0.20 294.84 3949.34 91.69 5501.19

7 190.008 0.20 300.00 3971.28 91.92 5514.92

8 190.008 0.20 294.84 3949.34 60.59 1454.21

9 190.008 0.20 294.84 3949.34 60.59 1454.21

10 190.008 0.20 294.84 3949.34 70.91 1276.32

11 190.008 0.20 294.84 3949.34 67.81 1220.58

12 190.008 0.20 294.84 3949.34 75.11 9013.18

13 190.008 0.20 294.84 3949.34 75.11 9013.18

14 190.008 0.20 294.84 3949.34 75.11 9013.18

15 190.008 0.20 294.84 3949.34 75.11 9013.18

16 190.008 0.20 294.84 3949.34 75.11 9013.18

17 190.008 0.20 294.84 3949.34 74.38 4462.81

18 190.008 0.20 294.84 3949.34 74.38 4462.81

19 190.008 0.20 294.84 3949.34 75.11 4462.81

20 190.008 0.20 294.84 3949.34 73.20 2927.91

21 190.008 0.20 294.84 3949.34 74.17 7120.37

22 190.008 0.20 294.84 3949.34 73.20 2927.91

23 190.008 0.20 294.84 3949.34 73.20 2927.91

24 190.008 0.20 294.84 3949.34 74.17 8900.46

25 190.008 0.20 294.84 3949.34 73.20 2927.91

26 190.008 0.20 294.84 3949.34 73.20 2927.91

27 190.008 0.20 294.84 2962.01 65.74 3944.60

28 190.008 0.20 294.84 2962.01 65.49 1964.59

29 190.008 0.20 294.84 2962.01 65.49 1964.59

30 190.008 0.20 294.84 2962.01 65.42 1962.51

31 190.008 0.20 294.84 2962.01 65.74 3944.60

32 190.008 0.20 294.84 2962.01 73.94 1478.89

33 190.008 0.20 294.84 2962.01 74.22 1484.47

34 190.008 0.20 294.84 2962.01 65.81 3948.76

35 190.008 0.20 294.84 2962.01 65.81 3948.76

36 190.008 0.20 294.84 2962.01 65.49 1964.59

Appendices v

Appendix D2: The information of landfill sites for construction and demolition waste

in Hanoi

No Landfill site Area (ha)

Capacity (Ton per

day) Company name

Distance (km)

0 Nam Son, Phu Dien, Soc Son district

83.5 4,000 URENCO 45.57

1 Song Phuong commune, Hoai Duc district

1.5 150 Thanh Cong company

22.1

2 Phung Town, Dan Phuong district


20.5

3 Minh Khai commune, Hoai Duc district


16.53

4 Vinh Quynh, Thanh Tri district

4.9 600 Technology and Ecology Joint Stock Company

14.32

5 Ta Thanh Oai, Thank Tri district

1.5 800-1,000 MESC company 18.16

6 Lam Du, Long Bien district

4.5 URENCO 8.43

7 Kieu Ky commune, Gia lam distric

14 150 URENCO 26.29

8 Ngoc Thuy, Long Bien district

URENCO 8.6

9 Xuan Son, Son Tay 83.7 1,200-1,300

Son Tay environment and urban construction company limited

50.31

10 Lien Ha, Dong Anh district URENCO 24.2

11 Van Noi, Dong anh district 7.5 800-1,000 URENCO 15.04

12 Nguyen Khe, Dong Anh district

1,000 Thanh Long environmental service company

21.36

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