Development of Guidelines and Specifications for Low ...research4cap.org/Library/TRL-2017-BackAnalysis... · The Development of Guidelines and Specifications for Low Volume Sealed

Development of Guidelines and Specifications for Low Volume Sealed Roads through Back Analysis

Phase 1 Stakeholder Workshop Report

5th – 6th April 2017

James Zihni

TRL Limited

RAF2069A

June 2017

The Development of Guidelines and Specifications for Low Volume Sealed Roads through Back Analysis

Page 2

The views in this document are those of the authors and they do not necessarily reflect the views of the Research for Community Access Partnership (ReCAP), TRL or Cardno Emerging Markets (UK) Ltd for whom the document was prepared

Cover Photo: Kenneth Mukura

Quality assurance and review table

Version Author(s) Reviewer(s) Date

1 J Zihni A Bradbury 7 June 2017

Les Sampson Jasper Cook

13 June 2017

2 J Zihni A Bradbury 19 June 2017

ReCAP Project Management Unit Cardno Emerging Market (UK) Ltd Oxford House, Oxford Road Thame OX9 2AH United Kingdom


Page 3

Abstract The Development of Guidelines and Specifications for Low Volume Sealed Roads (LVSR) through Back Analysis project involves the review of previous LVSR studies on the design and performance of pavements and materials in a variety of environments. The project is in three Phases. Phase 1 of the Back Analysis project involves the collection and processing of evidence relating to the performance of existing and previous LVSRs over the last forty years. The main activity during this phase was development of a Low Volume Roads (LVR) database containing data on LVSR sections in Sub-Saharan Africa and South East Asia that were collected over a number of decades, including aspects of their design, construction and maintenance that have influenced their in-service performance. Phase 1 of the project involved development of a research strategy for Phases 2 and 3 that will investigate data and knowledge gaps, and will undertake training and capacity building of regional researchers and practitioners in the use of the database. The purpose of this report is to record the proceedings of the Phase 1 Stakeholder Workshop held in Dar es Salaam, Tanzania from 5th to 6th April 2017. The workshop outlined activities undertaken in Phase 1 and the methodological approach for delivering Phase 2 and 3 of the project.


Page 4

Key words Regional Back Analysis, Sub-Saharan Africa, Low Volume Sealed Roads, Low Volume Roads, Performance of Low Volume Roads, Low Volume Roads Database.

RESEARCH FOR COMMUNITY ACCESS PARTNERSHIP (ReCAP)

Safe and sustainable transport for rural communities

ReCAP is a research programme, funded by UK Aid, with the aim of promoting safe and sustainable transport for rural communities in Africa and Asia. ReCAP

comprises the Africa Community Access Partnership (AfCAP) and the Asia Community Access Partnership (AsCAP). These partnerships support

knowledge sharing between participating countries in order to enhance the uptake of low cost, proven solutions for rural access that maximise the use of

local resources. The ReCAP programme is managed by Cardno Emerging Markets (UK) Ltd.

See www.research4cap.org


Page 5

Acronyms, Units and Currencies AfCAP Africa Community Access Partnership ARTREF African Road and Transport Research Forum AsCAP Asia Community Access Partnership CBR California Bearing Ratio DCP Dynamic Cone Penetrometer DRC Democratic Republic of Congo FWD Falling Weight Deflectometer IRAT Improving Rural Access in Tanzania IRI International Roughness Index LS Linear Shrinkage LVR Low Volume Road LVSR Low Volume Sealed Road LWD Light Weight Deflectometer MDD Maximum Dry Density OMC Optimum Moisture Content PI Plasticity Index PL Plasticity Limit PM Plasticity Modulus PP Plasticity Product ReCAP Research for Community Access Partnership SP Shrinkage Product SR Silica-Sesquioxides Ratio TRL Transport Research Laboratory


Page 6

Contents

Abstract .................................................................................................................................3 Key words ..............................................................................................................................4 1 Introduction ...................................................................................................................7

1.1 Background 7 2 Phase 1 Stakeholder Workshop .......................................................................................7

2.1 Attendance 7 2.2 Programme 7 2.3 Introduction to Back Analysis 8 2.4 Introduction to the Database 8 2.5 Discussion on Research Studies 8 2.6 Using the Database 9 2.7 Discussion on Gap Analysis 9 2.8 Next Steps 10

3 Outcomes of the Workshop .......................................................................................... 10 3.1 Remarks on the Database 10 3.2 Remarks on the Gap Analysis 11

4 Participant Feedback .................................................................................................... 12 Annex A: Workshop Participants .......................................................................................... 14 Annex B: Introduction to Back Analysis ................................................................................. 16 Annex C: Introduction to the Database ................................................................................. 22 Annex D: Research Studies ................................................................................................... 27 Annex E: Database Practical Demonstration Worksheet ........................................................ 30 Annex F: Gap Analysis .......................................................................................................... 32 Annex G: Plans for Phase 2, roll out and management of the database .................................. 36 Annex H: Workshop Evaluation Feedback ............................................................................. 44


Page 7

1 Introduction

1.1 Background

During the last 40 years there has been a great deal of information developed through research studies carried out by research organisations, consultants, and academic institutions about reducing the costs of low volume roads and making them more reliable. It is the purpose of this project to capture as much of the research data as possible and to preserve it in a database in a form that engineers and researchers can access and use in the future for further research and analysis. By including data from many different sources, the full range of all the factors that affect pavement performance can be quantified, thereby providing data sets that can be combined for more comprehensive analysis and to provide better specifications. The Phase 1 Stakeholder Workshop allowed for the dissemination of current findings, the opportunity to introduce the LVR Database to a wide variety of users and to facilitate discussion on plans for delivering Phases 2 and 3 of the project. This report should be read in conjunction with the Phase 1 Final Report, which can be found on the ReCAP website (www.research4cap.org). The Final Report outlines the methodological approach to Phases 2 and 3 in more detail, and adopts a revised approach to that which was presented at the Phase 1 Stakeholder Workshop and provided in the Annexes of this report.

2 Phase 1 Stakeholder Workshop

2.1 Attendance

The workshop was attended by 70 participants from AfCAP and AsCAP countries, the African Road and Transport Research Forum (ARTReF), Improving Rural Access in Tanzania (IRAT), government departments and private sector organisations. The attendance list is included in Annex A.

2.2 Programme

The workshop was split over two days. The programme for 5th April is shown in Table 1.The programme for 6th April is shown in Table 2.

Table 1: April 5th

Programme

Time Session Presenter Facilitator

13:30 – 14:00 Brief on the Regional Back Analysis Project J Rolt L Sampson

14:00 – 15:00 Introduction to the LVR Database and User Manual T Buckland J Zihni

A Bradbury

15:00 – 15:30 Break

15:30 – 17:00 Discussion of studies so far included into the database

J Rolt A Bradbury

http://www.research4cap.org/


Page 8

Table 2: April 6th

Programme

Time Session Presenter Facilitator

09:00 – 10:30 Hands-on experience with the database by participants

T Buckland J Zihni

A Bradbury

10:30 – 11:00 Break

11:00 – 12:30 Discussion of Gaps Identified K Mukura A Bradbury

12:30 – 13:30 Lunch

13:30 – 15:00 Plans for Phase 2, roll out and management of the database

J Rolt K Mukura

A Bradbury

15:00 – 15:30 Break

15:30 – 16:30 ARTReF Feedback TRL final Wrap-Up A Bradbury

16:30 – 17:00 Summary and Closing Ceremony AfCAP & Govt of Tanzania

2.3 Introduction to Back Analysis

There was a brief introduction to the project from a ReCAP perspective by the ReCAP Infrastructure Research Manager. This was followed by a presentation by the TRL Team Leader (see Annex B for a copy of the presentation). This presentation outlined the main project objectives of Research, Capacity Building, Knowledge Exchange, Uptake and Embedment. The Team Leader outlined the scope of work for Phase 1 of the project; including forming a group of Low Volume Roads experts, carrying out a desk study and workshops to identify potential data sources and developing and populating the database and user manual.

2.4 Introduction to the Database

Following on from the Team Leader’s presentation, the project data specialists gave a presentation on the features and functions of the database including a live demonstration of several features to workshop participants. This presentation focused initially on the database requirements, architecture and structure. Following on from the presentation, a live demonstration of the database was conducted, initially focusing on the reporting tools and then including data entry. The presentation concluded with a summary of functionality. A copy of the presentation is available in Annex C.

2.5 Discussion on Research Studies

The final presentation of the day was given by the TRL Team Leader. This session provided a detailed summary of the twenty two research studies that have already been entered into the database. The presentation illustrated the broad range of data that could be entered into the database. By

Figure 1: Scenes from the Workshop


Page 9

presenting the studies currently held in the database it allowed workshop participants to see how the database could be utilised in different scenarios and to evaluate if other research data is suitable for inclusion. A copy of this presentation is available in Annex D. After the current data sources had been presented a discussion was held to establish if any participating countries had appropriate low volume road performance data that could be included in the database. Representatives from several countries including the Democratic Republic of Congo (DRC), Kenya, Ghana, and Uganda expressed an interest in sharing data, and this shall be explored further in Phase 2 of the project. Several other points were raised by participants, including the following:

The possibility of a language barrier where research studies originate from non-English speaking countries,

Whether the quality of the data entered into the database should be assessed, or whether all data should be accepted for completeness,

How to define the characteristics of a low volume rural road in order to determine which research studies should be included in the database.

Outcomes of the workshop, including concluding remarks, are provided in Section 3 of this report.

2.6 Using the Database

The first session of the second day of the workshop was for participants to have hands-on experience with the database. TRL had prepared a worksheet for participants to complete for the exercise (See Annex E). The data specialists worked through the first few questions to give an understanding of the use of the tool before participants worked together to solve the rest of the questions. After the worksheet had been completed a discussion was held to gain feedback on the use of the tool to allow TRL’s Data Specialists to improve its functionality and usability. Overall, participants agreed that the LVR database is fully functional and the stakeholders were comfortable navigating and extracting data after the demonstration. Several suggestions for new features were obtained and implemented after the workshop, and these are outlined in Section 3.1.

2.7 Discussion on Gap Analysis

After the hands on session, a presentation on Gap Analysis was given. Following on from the presentation a discussion was held to determine if there were any more gaps that needed to be considered or addressed. The following key issues were raised:

There is a need to get data on the durability of surfacings in different situations, and this is a major gap,

The impact of tyre pressure on the performance of LVRs is largely unknown and this is important,

The significance of a road maintenance strategy or regime on the performance of LVRs is also largely unknown and maintenance data should be included in the database,

As-built data is important in evaluating performance of LVRs and such data should be included in the database,

Swell information is also lacking in most projects and it is important to collect such information for the database.

The presentation on Gap Analysis is available in Annex F.


Page 10

2.8 Next Steps

Following the gap analysis, a presentation was given on TRL’s plans for Phase 2 of the project (See Annex G). This outlined the key objectives and activities to be addressed in Phase 2 including field and laboratory tests, updating the database and reviewing LVR Specifications. Phase 3 was also briefly outlined, with the expected objectives of capacity building, dissemination and uptake and embedment explained. A discussion was held, which raised several key points that will need to be considered whilst carrying out the proposed Phase 2 plans including:

Results of tests can vary due to laboratories used and quality control in place. This needs careful consideration during any laboratory testing,

Further data capture is required to exhaust all sources of available data on low volume road research across the Africa region, and to optimise the functionality of the database,

Only once all existing data is captured and a full and complete gap analysis is undertaken should fieldwork be undertaken for additional data collection,

Different countries use different standards – which standards should be used as the benchmark.

In summary the workshop was invaluable in provoking later discussion on the way forward, which has been incorporated into the Final Report.

3 Outcomes of the Workshop The issue of hosting the database in the future was discussed. The African Road and Transport Research Forum (ARTReF) expressed that they are happy to host the LVR database, and they shall discuss the practicalities of this role at the next ARTReF General Assembly. Additionally it was noted that in order to succeed, the project and database need promotion, commitment and financing. Other conclusions related to the database and gap analysis are also summarised as follows:

3.1 Remarks on the Database

1. The LVR database is fully functional and the stakeholders were comfortable navigating and extracting data after a demonstration workshop.

2. Significant amounts of data could still be added to the database.

3. There were AfCAP partner countries willing to partake in the population of the database including DRC, Kenya, Ghana, Uganda, etc.

a) Uganda is currently aggregating research data and information of past research work and these would be available for the LVR database.

b) There is also a possible source of information from Nigeria on ‘Engineering Properties of Subgrade Soils’.

c) DRC has data dating back decades which could be explored.

d) InfraAfrica has data from Malawi which can be included in the database.

4. The ongoing performance monitoring projects under AfCAP are a good source of data for the database.

5. Obtaining data would require some form of permission to ensure compliance with intellectual property rights and copyright.

6. Sources of data should be included in the database and this would be vital for future reference.


Page 11

7. It was suggested that mapping visualisation or GPS information should also be included in the database where possible.

8. Some of the comments relating to the use of the database include the following:

a) There is need for capability in the architecture of the database to do a named search,

b) It was hard to keep track of the searches in the various layers of data and it would be good if the database could do the tracking and have a window which shows the information to the user,

c) There is need to specify the table which is required during querying and exportation of data from the database. There is also need to include right click to obtain additional information which should be in the background,

d) There should be capability to sort the data in alphabetical or other logical order,

e) Basic data which will more commonly be required by users should be included in the database e.g. Atterberg limits should include LL, PL and PI not only LL or PI and LL only,

f) There is need for a code for the material source i.e. where the materials which were tested or investigated came from,

g) There is need to set up standard queries to assist the users and/or flexibility in the report design templates,

h) Creating a bulk upload tool for data.

The following updates to the website have been made since the workshop:

1. Amended some of text labels based on feedback from experts and users,

2. Allowing reviewers to more easily locate and access attachments,

3. Update to layout of reports page,

4. Including a record for user data downloads in the audit log,

5. Ability to delete user accounts from database,

6. Allowing Administrators to reset passwords,

7. Adding Terms and Conditions for use of downloaded data,

8. Checking functionality on Android devices.

Some of the more comprehensive updates (e.g. including GIS functionality, creating a bulk upload data tool, creating custom report templates) should be reviewed in Phase 2 to understand the effort required and if they should be incorporated into the website.

3.2 Remarks on the Gap Analysis

The following key issues were raised:

1. There is need to get data on durability of surfacings in different situations and this is a major gap.

2. The impact of tyre pressure on the performance of LVRs is largely unknown and this is important.

3. The significance of a road maintenance strategy or regime on the performance of LVRs is also largely unknown and maintenance data should be included in the database.


Page 12

4. As-built data is important in evaluating performance of LVRs and such data should be included in the database.

5. Swell information is also lacking in most projects and it is important to collect such information for the database.

4 Participant Feedback Workshop participants were provided with an evaluation form and invited to score aspects of the workshop proceedings from 1 (poor) to 5 (excellent). The Back Analysis workshop received an average score of 4.2, and Table 3 summarises the average scores for each session.


Page 13

Table 3: Summary of Workshop Evaluation Questionnaire

Evaluation Questions Average Score No. of Responses

1. Please list three things that you have learned during

this workshop (Text question - see Annex H)

2. How would you rate the overall usefulness of this

workshop?

4.5 42

3. To what extent did the workshop meet your

expectations?

4.2 43

4. Were you as participant able to effectively contribute

to the different sessions of the workshop?

3.8 43

5. How do you rate the workshop schedule/timetable? 4.3 43

6. What was your impression of the logistical

organisation and management of the workshop?

4.1 43

BACK ANALYSIS

13. What was your impression of the presentation on

the Regional Back Analysis project?

4.2 43

14. How would you rate the presentation on the LVR

Database and User manual?

4.2 42

15. What was your impression of the presentations by

participants on the database?

4.0 43

16. What was you impression of the plans for phase 2

of the project?

4.2 42

17. What were the two best and most useful aspects of

the workshop? (Text question - see Annex H)

18. How could the workshop have been improved?

(Text question - see Annex H)

19. Do you have any other comments or suggestions?

(Text question - see Annex H)

A full summary of text responses to questions 1, 17, 18 and 19 is provided in Annex H. Please note that the feedback responses also cover the ReCAP Climate Resilience and Adaptation workshop that was held in the two days preceding the Back Analysis workshop at the same venue in Dar es Salaam. Overall the feedback was very positive, and the database demonstration was particularly well received:

“The hands-on use of the TRL database software was my highlight of the workshop. It is hoped that arrangements will be made to house the software with regional points (ARTREF) so that tests carried out on LVR should be deposited and used for evaluation and further investigation and research.”

Participants also recognised the importance of data capture, with many wishing to share their experiences of LVR data collection from other countries. The database was viewed by some as a way of providing evidence for considering changes to LVR specifications, to enable construction of low volume roads at lower cost.


Page 14

Annex A: Workshop Participants

Name Country

AFCAP Countries (22) Hillary O.Akwiri Kenya

Hillary K. Cherop Kenya

Peter Kome Sierra Leone

Don Kuubeterzie Ghana

Efua Duma Akweetea-Mensah Ghana

Margaret T Sarsih Liberia

Alibaba K Kpakolo Liberia

Zerai Hadera Ethiopia

Ehitabezahu Niguissie Ethiopia

Billy Tshibambe DRC

Joshua Mutia Mwindo DRC

Joseph Haule Tanzania

Vincent Lwanda Tanzania

Alice Chipasula Zambia

Sharmey Banda Malawi

Willard Kaunde Malawi

Moises Dzimba Mozambique

Raquel Langa Mozambique

Joel Webster Mbujje Uganda

Mark Henry Rubarenzya Uganda

John Kenyi Sasa South Sudan

Philip Marlow South Sudan

ASCAP Countries (4) Kyaw Swe Myanmar

Zaw Min Thike Myanmar

Md. Abul Kalam Azad Bangladesh

Ripon Hore Bangladesh

ARTREF (13) Simon Oladele Botswana

Ashley F Kanyoza Malawi

Kelvin Mphonda Malawi

Presley Chilonda Zambia

M Cataeno Zimbabwe

Immaculate Katutsi Uganda

George N Omange Nigeria

Jeremiah Turic Bairiak South Sudan

Fikiri Magafu Tanzania

Benoit Verhaeghe South Africa


Page 15

Edmund Debrah Ghana

Jospeh Busu South Sudan

Irene Langa Simoes Mozambique

PMU (7) Gerome Rich UK

Jasper Cook UK

Les Sampson South Africa

Paulina Agyekum Ghana

Nkululeko leta South Africa

Nandar Kyaw Myanmar

Julie Gibson UK

IRAT (1) Tom Bishop

Tanzania Nominations (15) Clement Ngirwa Tanzania

Rahma Mwinyi Tanzania

University of Dar es Salaam - one Participant Tanzania

Nicolas D. Francis Tanzania

Eliud T Nyauhenga Tanzania

Rashid Kalimbaga Tanzania

Patrick Barozi Tanzania

Joseph Mnkeni Tanzania

Simon T. Njau Tanzania

National Environmental Management Council - One Participant Tanzania

Benjamin Maziki Tanzania

Abdul Digaga Tanzania

Josephat Nestory Shehemba Tanzania

Dar Es Salaam Institute of Technology Tanzania

Elina Kayanda Tanzania

Technical Panel (1) Tony Greening UK

Back Analysis Team and Specialists (7) Phil Paige Green South Africa

John Rolt UK

Tom Buckland UK

James Zihni UK

Kenneth Mukura Zimbabwe

Annabel Bradbury UK

Mike Pinard Botswana


Page 16

Annex B: Introduction to Back Analysis


Page 17


Page 18


Page 19


Page 20


Page 21


Page 22

Annex C: Introduction to the Database


Page 23


Page 24


Page 25


Page 26


Page 27

Annex D: Research Studies


Page 28


Page 29


Page 30

Annex E: Database Practical Demonstration Worksheet

Back Analysis Hands on experience

Information points on pages are denoted by an ‘i’ symbol. These will give quick tips on the

functionality of the page. These points also give references to applicable sections in the user manual.

At any point the user manual can be access by clicking ‘Help’ in the banner. This opens on a new

page. The contents page of the manual enables quick navigation of the document by clicking on the

desired section.

1)

a) Filter Country for Botswana, Layer to Base, Property to Strength (CBR). How many rows are returned?

b) Add sub-base to Layer selection, reselect Strength (CBR) for Property. How many rows are returned?

c) Clear the Layer filter; reselect Strength (CBR) for Property. How many rows are returned?

d) Clear all filters.

2) a) Filter Data Source to Analysis of Botswana Pavement Monitoring Sections. How many rows

are returned?

b) Add PESE 1 and PESE 2 to Sections filter. How many rows are returned?

c) Add Sand to Materials filter. How many rows are returned?

d) Add Atterburg Limits to Property selection. How many rows are returned?

e) Clear all filters.

3) a) Select Botswana and Ghana in Country filter, Subgrade for Layer selection and the Atterburg

Limits in Property. How many rows are returned?

b) Change Property to Moisture. How many rows are returned?

c) Clear all filters.

4) a) Select Zambia and Zimbabwe, Base, Cracking. How many rows are returned?

b) Change Base to Sub-base, keep Property as Cracking. How many rows are returned?

c) Clear all filters.


Page 31

5) What is the Plastic Limit of the Subgrade on the NIBU Section for the Ugandan Engineering Standards Project?

6) What is the Moisture Content in the Base layer, Left Hand Lane, Inside Wheel Track for the Section WAMI 1?

7) Create a report on the Moisture for all studies in Botswana. Further analysis can be carried out in Excel. To do this, select the Excel button below ‘Select files to export’. Open the downloaded file. A warning message will show querying the file extension. Click ‘Yes’. Select ‘Enable Editing’ in the yellow Excel banner. The file is now ready to be used in Excel.

8) Files can also be exported in .csv format. Select the Maypen Bypass Study and click the ‘csv’ button. This will download the study in .csv format.


Page 32

Annex F: Gap Analysis


Page 33


Page 34


Page 35


Page 36

Annex G: Plans for Phase 2, roll out and management of the database


Page 37


Page 38


Page 39


Page 40


Page 41


Page 42


Page 43


Page 44

Annex H: Workshop Evaluation Feedback


Page 45


Page 46


Page 47


Page 48


Page 49


Page 50


Page 51

Documents

Development of Guidelines and Specifications for Low ...research4cap.org/Library/TRL-2017-BackAnalysis... · The Development of Guidelines and Specifications for Low Volume Sealed