PERFORMANCE OF LIGHTWEIGHT FOAMED CONCRETE USING

PERFORMANCE OF LIGHTWEIGHT FOAMED CONCRETE USING

LATERITE AS SAND REPLACEMENT

KHAW YONG HUI

A report submitted in fulfillment the

requirement for the award of degree of

Bachelor of Civil Engineering

Faculty of Civil Engineering & Earth Resources

Universiti Malaysia Pahang

December 2010

ABSTRACT

Lightweight foamed concrete (LWC) has been successfully used and it has

gained popularity due to its lower density than conventional concrete. It is created by

uniform distribution of air bubbles throughtout the mass of concrete. Recently, most

studies on LWC concern on the influence of filler type and the particle size of sand

on the strength. In this study, the strength of LWC with density 1400 kg/m 3 was

produces due to different percentage of laterite as sand replacement. Four series of

LWC mix designs with ratio 2:1:1 comprises of 0%, 5%, 10% and 15% as sand

replacement (by total weight of sand) were considered. Two types of testing were

conducted namely compressive strength and modulus of elasticity (MOE). The tests

were prepared in order to determine the effect of using different percentage of laterite

due to different curing ages. The results revealed that, increasing the percentage of

laterite as sand replacement, the strength improves significantly due to compressive

strength and MOE for all mixes. It also indicated that the curing ages significantly

affect its strength. However, it is noted that the optimum mix design to produce

LWC-Laterite was obtained by using 5% of laterite as sand replacement.

V

ABSTRAK

Konkrit buih berongga (LWC) telah digunakan secara meluas dan mendapat

sambutan yang baik kerana ketumpatannya lebih rendah berbanding dengan konkrit

biasa. Ia dicipta dengan pengagihan yang seragam dari gelembung udara rnelalui

jisirn konkrit. Pada masa kini, kebanyakan kajian telah dijalankan terhadap konkrit

buih berongga yang mempengaruhi kekuatannya dari pelbagai segi jenis dan saiz

butiran pasir. Dalam kajian mi, kekuatan mampatan konkorit buih berongga dengan

ketumpatan 1400 kg/M3 telah dihasilkan dengan rnenggunakan perbezaan peratusan

latent sebagai pasir gantian. Empat siri konkrit buih berongga telah disediakan

dengan campuran nisbah 2:1:1 akan diggantikan dengan peratusan latent yang

berbeza iaitu 0%, 5%, 10% dan 15% sebagai pasir gantian daripada jurnlah berat

pasir sebenar. Dua jenis ujian dijalankan iaitu kekuatan rnarnpatan dan modulus

elastik. Perlaksanaan ujian mi adalah untuk menentukan kesan-kesan dan

penggunaan peratusan latent dengan masa pengawetan yang berbeza. Keputusan

danipada kajian mendedahkan, kekuatan mampatan dan modulus elastik konkrit buih

berongga meningkatkan apabila peningkatan peratusan latent sebagai pasir gantian.

Peningkatan masa pengawetan akan mempengaruhi kekuatan mampatan konknit buih

berongga. Walaubagaimanapun, didapati rekabentuk campuran yang optima untuk

menghasilkan konkrit buih berongga dengan latent adalah campuran yang

mengandungi 5% latent.

vi

TABLE OF CONTENTS

CHAPTER ITEM

TITLE

DECLARATION

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

ABSTRAK

TABLE OF CONTENTS

LIST OF TABLES

LIST OF FIGURES

CHAPTER 1 INTRODUCTION

1.1 Background of Study

1.2 Objective of Study

1.3 Problem Statement

1.4 Scope of Study

CHAPTER 2 LITERATURE REVIEW

2.1 Introduction

2.2 Historical Development of Lightweight Foamed Concrete

2.2.1 Application of Foam Concrete

2.3 Compressive Strength

2.4 Factor Affecting the Compressive Strength of Foam Concrete

PAGE

11

111

iv

v

vi

vii

x

xli

1

3

3

4

8

8

11

12

viii

2.4.1 Different Density of Lightweight Foamed Concrete 12

2.4.2 Different Curing Day 13

2.4.3 Effect of Compressive Strength Due to Different Percentage of Fly Ash 14

2.5 Mechanical Properties of Lightweight Concrete 14

2.5.1 Fire Resistance 15

2.5.2 Modulus of Elasticity 15

2.6 Material Properties of Lightweight Foamed Concrete 16

2.7 Advantages of Lightweight Foamed Concrete 17

2.8 Introduction of Laterite 18

2.9 Properties of Laterite 19

2.9.1 Density of Laterite 19

2.9.2 Specific Gravity 20

2.9.3 Durability 20

2.9.4 Crushing strength 21

2.10 Properties of Shape and Texture 21

CHAPTER 3 METHODOLOGY 23

3.1 Introduction 23

3.2 Material Selection 25

3.2.1 Cement 25

3.2.2 Water 26

3.2.3 Sand 27

3.2.4 Laterite 28

3.2.5 Foamed Agent 29

3.3 Preparation of Specimen 29

3.3.1 Preparation of Specimen 30

3.3.2 Determination Weight of Raw Materials 33

3.4 Mix Proportion 33

3.4.1 Foamed Concrete Mix Design 33

3.5 Curing Method 34

3.5.1 Air Curing 34

3.6 Sieve Analysis Testing 34

ix

3.7 Liquid Limit Test 35

3.8 Plastic Limit Test 37

3.9 Compressive Strength 38

3.9.1 Compressive Strength Testing Procedure 38

3.10 Modulus of Elasticity 39

CHAPTER 4 RESULTS AND DISCUSSIONS 41

4.1 Introduction 41

4.2 Particle Size Analysis of Laterite 42

4.3 Atterberg Limits Analysis of Laterite 44

4.3.1 Plastic Limit 44

4.3.2 Liquid Limit 45

4.4 Effect of Compressive Strength of LWC-Laterite due to Different Curing Ages 46

4.4.1 Compressive Strength of Lightweight Foamed Concrete Due to Different Curing Ages 47

4.4.2 Discussions on Effect of LWC-Laterite at Different Curing Ages subjected to Compressive Strength 51

4.5 Compressive Strength of LWC due to Different Percentage Laterite as Sand Replacement. 54

4.5.1 Discussion on Effect of LWC-Laterite at Different Percentage of Laterite subjected to Compressive Strength 57

4.6 Discussion on Modulus of Elastic of LWC-laterite at Different Curing Ages 60

4.7 Discussion on Modulus of Elastic of Foamed Concrete with Laterite as Sand Replacement due to Different Percentages 61

CHAPTER 5 CONCLUSIONS AND RECOMMENDATIONS 64

5.1 Introduction 64

5.2 Conclusion 65

5.3 Recommendations 66

REFERENCES 67

LIST OF TABLES

TABLE NO TITLE PAGE

1.1 Numbers of Cube Specimens Replace with Laterite 5

1.2 Numbers of Cylinder Specimens Replace with Laterite 5

2.1 Application of Foamed Concrete 10

2.2 The Typical Properties of Lightweight Foamed Concrete 16

3.1 Numbers of LWC-Laterite with Density of 1400 kg/M3 30

3.2 Weight of Raw Materials for LWC in 1m 3 33

4.1 Sieve Analysis Data of Laterite 43

4.2 Result on Plastic Limit Test for Laterite 44

4.3 Result on Liquid Limit Test for Laterite 45

4.4 Result on Compressive Strength at 7 Days of Curing Age 47



4.7 Summary Result on Compressive Strength of LWC-Laterite at Different Curing Ages 53

4.8 Result on Compressive Strength of LWC with 0% of Laterite 54



x

xi


4.12 Summary Result on Compressive Strength for LWC-Laterite at Different Percentage of Laterite 59

4.13 Summary Result on Modulus of Elasticity for LWC-Laterite at Different Curing Ages 60

4.14 Summary Result on Modulus of Elasticity for LWC-Laterite at Different Percentages of Laterite 62

LIST OF FIGURES

FIGURE NO TITLE

PAGE

2.1 Compressive Strength Development of Cellular Concrete Mixture 14

2.2 Laterite Soil distribution of world 18

2.3 Shape of Laterite 22

3.1 Flow Chart of Progress 24

3.2 Ordinary Portland Cement (OPC) 26

3.3 Water 27

3.4 Sand 27

3.5 Laterite 28

3.6 Protein Foams Tend to have an off white color 29

3.7 Steel Mould of LWC Cube 31

3.8 Steel Mould of LWC Cylinder 32

3.9 Analysis Test Equipment 35

3.10 Atterberg Limit Test Equipment 36

3.11 Compressive Strength Test machine 39

3.12 Modulus of Elasticity Machine 40

4.1 Grain Size Distribution Curve for Laterite 43

4.2 Graph on Penetration Cone versus Moisture Content of Laterite 46

4.3 Compressive Strength of LWC-Laterite at 7 Days of Curing Ages 48



xii

4.6 Compressive Strength of LWC-Laterite- at Different Curing Ages 53

4.7 Compressive Strength of LWC with 0% of Laterite 54




4.11 Summary Result on compressive Strength for LWC-Laterite at Different Percentage of Laterite 59

4.12 Modulus of Elastic for LWC-Laterite at Different Curing Ages 61

4.13 Summary Result on Modulus of Elastic for LWC-Laterite at Different Percentages of Laterite 63

xlii

CHAPTER 1

INTRODUCTION

1.1 Background of Study

Concrete is known as a common material which is widely used in the

construction industry, from basic work to multi-storey building and mega structure.

Concrete is a material where mixture by cement, water, and aggregate (fine and

coarse) which must be workable, resistance to freezing, chemicals resistance, low

permeability, wear resistance, and economy (Metha & Monteiro, 2006).

Lightweight foamed concrete was used nearly a century ago in the special

precast application of autoclaved aerated concrete, with the first reported applications

being two apparently independent initiatives in 1923, one in Denmark the other in

Sweden. In this application, the entrained gases is actually produced by the

generation of hydrogen gas using powdered aluminum in a slurry mix made alkaline

by the inclusion of Portland cement and sometimes lime addition

(Beningfield et al., 2005).

2

Lightweight foamed concrete based on this concept began to adopted in the

early 1980's and at that., time take up began to accelerate in much of Europe with

Germany in particular leading the way. Within the UK specifications began to appear

in the early 1990's and the market has continued to grow rapidly, with current

estimates of perhaps 300,000 in to 350,000rn3 per annual used in the UK (Gaimster

et al., 2005).

Aldridge (2005) stated that, lightweight foamed concrete is more popular

usage in the construction field due to reduce the cost, lightness and easy to work in

this field. In its basic form foamed concrete is blend of sand, cement, and water (the

base mix) and a pre-formed foam, which in itself is a mixture of foaming agent

(either synthetic or protein based), water and air.

Lightweight concrete also know as foamed concrete which is lightweight

material formed by entrapping or generating small bubbles of air into Portland

cement mix by mechanical or chemical means. Lightweight foamed concrete with

density from 400 kg/rn3 to 1800 kg/m3 can be produced strength up to 12 MPa.

Characteristics of lightweight foamed concrete is depends on the mix design there

are however a number of general properties which are constant across a range of mix

designs are high strength to weight ratio, low coefficient of permeability, low water

absorption, good freeze/thaw resistance, high modulus of elasticity, low shrinkage,

thermal insulating properties, and fire resistance.

This study is important to determine the performance of lightweight foamed

concrete by adding various percentages of laterite as sand replacement by weight of

sand and determine compressive strength of it and determine the effect of using

different percentages of laterite as sand replacement to lightweight foamed concrete.

3

1.2 Objectives of Study

The objectives of this study are: -

i. To determine the compressive strength of lightweight foamed concrete with

different percentage of laterite (LWC-Laterite) as sand replacement.

ii. To determine the modulus of elasticity of lightweight foamed concrete with

different percentage of laterite (LWC-Laterite) as sand replacement.

iii. To determine the effect of using different percentage of laterite as sand

replacement to lightweight foamed concrete.

1.3 Problem Statement

The ways to control the density of lightweight foamed concrete become

difficult. By using different quantities of foamed agent will affect the strength and

quality of foam concrete.

Through this problem, one of the solutions suggested is the use of laterite as

sand replacement with a portion by total weight of sand. Lightweight foamed

concrete can be made cheaper by replacing some of sand with laterite.

Currently, problem is every construction was using the river sand as their

main material to construct the element of building that be less of river sand in green

mother nature. In this study, using the laterite as sand replacement could be use to

4

overcome this problem. To determine the optimum percentage of laterite as sand

replacement to get the maximum strength of the lightweight foamed concrete.

1.4 Scope of Study

In this study, the lightweight foamed concrete were produced to investigation

the compressive strength and modulus of elasticity using different percentage of

laterite as sand replacement. The percentage of laterite as sand replacement by total

weight of sand such as 0%, 5%, 10% and 15%. Laterite were mixed with cement,

fine aggregate, water and foam agent. The design of density for lightweight foamed

concrete must be obtained is 1400 kg/M3 with mix proportion ratio 2:1:1 comprises

of cement to sand to water ratio 0.5. Otherwise, the lightweight foamed concrete

without sand replacement were design as a control mix.

36 cubes concrete were prepared to be test on compressive strength and

36 cylinders are prepared to be test on modulus of elasticity. Minimum three samples

will be prepared for each parameter and the sample must accordance to

BS: 1881: Part 108: 1983 for 0%, 5%, 10% and 15%. For cubes and cylinder have

the dimension 150 mm x 150 nm-i x 150 mm and 150 mm x 300 mm respectively. All

the specimens were tested after expose to air curing at 7, 28, 60 days. The number of

sample prepared as shown in Tables 1.1 and 1.2.

After the specimens matured at the followed curing days, the compressive

test and modulus of elasticity was conduct in the FKASA Laboratory. The method of

testing is according to the BS: 1881: Part 116: 1983.

Table 1.1 Numbers of Cube Specimens Replace with Laterite

Mix PrOPortlOfl Percentage of Numbers of sample (cubes)

Mix Designlaterite "° Cement: sand:

water7 days 28 days 60 days

(Control) 3 3 3

1400 kg/m' 2: 1 :15 3 3 310 3 3 3 15 3 3 3

Table 1.2 Numbers of Cylinder Specimens Replace with Laterite

Mix proportionPercentage of

N Numbers of sample (cylinder) Mix Design

laterite '°) Cement: sand: water

7 days 28 days 60 days

(Control) 3 3 3

1400 kg/M3 2: 1 :15 3 3 310 3 3 3 15 3 3 3

CHAPTER 2

LITERATURE REVIEW

2.1 Introduction

Conventional concrete made with natural aggregate originating from hard

rock has a high density lies within the range of 2200 to 2260 kg/M3 and represents a

large proportion of the dead load on a structure. According to BS: 8110: Part 2: 1985

classifies the lightweight foamed concrete is one with a density of 2000 kg/M 3 or less.

Lightweight foamed concrete can be gaseous or foamed concrete that uses specially

prepared chemicals; it can be a no-fines concrete that uses ordinary gravel or crushed

stone, a normal-weight aggregate concrete with an excessive amount of entrained air,

or a concrete that is made from lightweight aggregates.

Lightweight foamed concrete is a class of aerated concrete. Aerated concrete

can be classified according to the methods and agents used to introduce air in the

concrete. Aerated concrete can be produced by introducing air entraining agent, gas

forming chemicals and foaming agents. Concrete which is aerated using foaming

agent is known as lightweight foamed concrete. Foaming agents can be synthetic

based or protein based.

7

The use of lightweight foamed concrete offer many benefits and

advantageous particularly cost saving, fast completion and easy application

compared to other materials such as steel and timber. Lightweight foamed concrete is

characterized by its low compressive strength and high insulation against heat and

sound. The compressive strength and other functional properties of lightweight

foamed concrete are greatly influenced by the amount of air content introduced by

foaming agents.

The application of lightweight foamed concrete in civil engineering works is

very broad as it can be used in almost every parts of building from the superstructure

right down to the substructure, including wall panels and roofing. Any conventional

panels or masonry units used for load and non-load bearing walls using normal

concrete can be replaced directly by foamed concrete panels and units. Very low

density lightweight foamed concrete can be used as thermal and sound insulation

panels, filtering media and floating blocks for fishery purposes.

Lightweight foamed concrete can also be used to cast elements for

architectural purposes, pottery, void filling, trench reinstatement, foundation raising

and swimming pool. In highway construction, lightweight foamed concrete can be

applied as soil filling for sub-base, bridge abutments and bridge embankment. It is

worth noting that the use of lightweight foamed concrete is popular in other countries

such Europe, Japan and United Kingdom.

8

2.2 Historical Development of Lightweight Foamed Concrete

Romans in the second century where 'The Pantheon' has been constructed

using pumice, the most common type of aggregate used in that particular year

(Samidi, 1997). Since then, the use of lightweight foamed concrete has been widely

spread across other countries such as USA, United Kingdom and Sweden. In UK,

10 years ago the usage of lightweight foamed concrete has grown more rapidly than

any other "special" concrete product. Lightweight foamed concrete can be defined

as a type of concrete including an expanding agent in that it increases the volume of

the mixture while giving adding qualities such as fallibility and lessened the dead

weight (Zakaria, 1978). Lightweight foamed concrete is 87% to 23% lighter than the

conventional concrete with. a dry density from 300 kg/M3 up to 1840 kg/m3 . The

main specialties of lightweight foamed concrete are its low density and thermal

conductivity. Its advantages included reduction of dead load, faster building rates in

construction and lower haulage and handling costs.

2.2.1 Application of Foam Concrete

Rudnai et al., (1963) and Narayanan et al., (2000) stated that lightweight

foamed concrete also includes in structural elements, non structural partitions and

thermal insulating materials. Manufacturers developed lightweight foam concretes of

different densities to suit the above requirements. The density of lightweight foamed

concrete ranges from 300 kg/M3 to 1800 kg/M3 and these products were used in

trench reinstatement, bridge abutment, void filling, roof insulation, road sub-base,

wall construction, tunneling etc.

9

According to Gao et al., (1997) noted that self weight represents a very large

proportion of total load on the structure, and there are clearly considerable

advantages in reducing the density of concrete in concrete construction. A decreased

density of concrete for the same strength level permits a saving in dead load for

structural design and foundation.

Lightweight foamed concrete can be applied in the field of construction such

as: in lightweight bricks or blocks for high-rise buildings, in panels and partition

walls of various dimensions either pre-cast or poured in place, cast in-place for a unit

of low cost terrace houses and bungalows, in all types of insulation works, including

cavity walls, in roofing and ceiling panels, in sound proofing application, in pre-cast

industrial and domestic building panels, both internal and external, in pre-cast or in-

place exterior wall facades for all sizes of buildings, in foundations for roads and

sidewalks, in sub-surface for sport arenas, e.g. tennis courts, in infihl sections

between beams of suspended floors, in aircraft arresting beds, in crash barriers, in

explosion-resistant structure, in highway sound barriers and in floating barge, jetties,

walkways, fish cages and floating homes.

Lightweight foamed concrete (LWC) has several and always increasing

applications in all types of construction work. Some of the most common

applications are shown in Table 2.1.

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Table 2.1: Application of Foamed Concrete

Source: Neville, 1985

Applications

Lightweight and insulating cements for floors foundation, for

heat insulation and slope for flat roofs, rigid floors foundation,

tennis courts foundation, interspace concrete filling, raceways

insulation; thermo insulating blocks, steel structures 300 to 600 kg/rn3

fireproofing, tunnels and pipelines compensating mass, dumps,

foundation and coverings land reclamation and consolidation

underground cavities infill and all types of infill where an

elevated thermal insulation is required.

Stables and pig-sties foundations; industrial foundations,

600 to 900 kg/M3 partition and tampooning slabs, ceiling slabs, concrete and

Lightweights Concrete mixed panels.

Blocks for outside walls, slabs for partitions, concrete and light

900 to 1200 kg/ml weight concrete mixed panels for covering, foundations for

elastic floors.

Prefabricated panels for civil and industrial buildings plugging; 1200 to 1700 kg/M3

walls casting, gardens ornaments.

In Malaysia the first major application of lightweight foamed concrete in

Malaysia is at the SMJ\RT tunnel project in Kuala Lumpur. The lightweight foamed

concrete specified was density 1800 kg/rn3 which achieved compressive strength of

3 N/mm2 at the age of 28 days. Otherwise lightweight foamed concrete inert, finely

divided materials such as powdered waste plastic, rice husk and other locally

available biomass are also being experimented. The composition is proposed to be

injected at prescribed locations with innovative precast lightweight hollow-core

concrete pile to effect replacement of portions of the soft soil.. The system is expected

to provide cost effective geotechnical solution as the surrounding soft ground

becomes compacted while foamed concrete solidifies in situ. Foundation system with

the utilization of used tyres are being experimented in some housing project in

Malaysia. Successful deployment of-the system is expected -to -provide a fast. track

11

method for affordable quality assured housing. The system is applicable for the

homeless people who urgently need a decent shelter. Technical specification has:

been prepared for an industrialized building system complying with modular

coordination (Lee, 2005).

2.3 Compressive Strength

Kearsley (2000) stated that the compressive strength decreases exponentially

with a reduction in density of foamed concrete. The compression strength will be

influenced by the specimen size and shape, the method of pore formation, direction

of loading, age, water content, characteristics of ingredients used and the method of

curing. According to Aldridge (2005) found that, the mixture ratio between the

cement, water and sand, curing regime, type and particle size distribution of sand and

type of foaming agent used also will affecting the strength of foam concrete.

Kearsely (2000) noted that dry density of foam concrete between 500 kg/m3

and 1000 kg/rn3 , the compressive strength decreases with an increase in void

diameter. For densities higher than 1000 kg/M3, as the air-voids are far apart to have

an influence on the compressive strength, the composition of the paste determines the

compressive strength. Jones et al., (2005) reported that small changes in the water to

cement ratio does not affect the strength of foam concrete but the compression

strength increased due to higher water and cement ratio.

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2.4 Factor Affecting the Compressive Strength of Foam Concrete

The compressive strength of lightweight foamed concrete is depend on many

factors such as the sand to cement ratios (s/c), curing duration, water to cement ratios

(w/c) and particle size distribution of sand. In this present section, the factor affecting

the compressive strength of lightweight foamed concrete will be discussed.

2.4.1 Different Density of Lightweight Foamed Concrete

Hamidah et al., (2005) studied on compressive strength of lightweight

foamed concrete mix of different sand cement ratio and curing conditions was shown

the compressive strength of lightweight foamed concrete increases as the density

increases and sand-cement ratio decreases. That is means lower-density lightweight

foamed concrete can achieve a strength equals to higher density foamed concrete by

increasing the cement content. Otherwise cheaper mix of foamed concrete would

only be possible at higher sand content. In a lower density foamed concrete, the

amount of sand also limited to avoid segregation and collapse of the mix.

Generally, the density of a porous media is dependent on the amount of pores

and pores Size distribution in the media. It would have been expected therefore, that a

higher density foamed concrete would record a higher compressive strength therefore,

that a higher density foamed concrete would record a higher compressive strength

due to its lower porosity. Narayanan (2000) studied the relationship between pore

Size and compressive strength. They concluded that the compressive strength is

dependent on the amount or distribution of pores and pore sizes. The size and the

amount of pores influence the compressive strength of a porous material, with

smaller size air pores leading to higher compressive strength (Tang, 1986).

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2.4.2 Different Curing Day

For lightweight foamed concrete (LWC), curing plays an important role for

strength development. In this study, the compressive strength was tested at different

curing condition of the LWC, which are water and air curing. The samples were

cured in three different ages before test the specimen, namely 7 days, 28 days, and

90 days.

Once more it proves that the strength for air cured sample is higher than

water cured sample (Shan, 1995). More Durable Concrete Good concrete, properly

cured, has fewer pores and crevices where water can enter, freeze, expand and crack

the concrete. Air entrainment helps make more durable concrete, but its use must

also be accompanied by proper curing.

Improper curing can easily the strength of even the best lightweight foamed

concrete by 50%. Curing simply means keeping the water in the lightweight foamed

concrete where it can do its job of chemically combining with the cement to change

the cement into tough "glue" that will help develop strong, durable concrete. Good

curing means keeping the LWC damp and above 50° F (10° C) until the foamed

concrete is strong enough to do its job (Anon, 2009a).

C-

284 E, DAYS

PC/60%FA

PC/40%FA

Ref. PC

90-d

(:11.5

L3

0

0.5 0

0

7-d.

14

2.4.3 Effect of Compressive Strength Due to Different Percentage of Fly Ash

The strength development with time of all the foamed concretes as shown in

Figure 2.1. Overall strength between 0.5 MPa and 2 MPa were observed, exception

of Portland cement with the 70% Fly Ash after 90 days of curing. Portland . cement!

Fly Ash mixes achieved strengths greater than that of the reference Portland cement

concrete. In addition, whilst the Portland cement foamed concrete strength remained

fairly constant between 28 and 90 days, the strength of the Portland cement / Fly Ash

mixes contained to increase beyond 28 days (Papayianni, 2005).

2.5

Figure 2.1: Compressive Strength Development of Cellular Concrete Mixtures

2.5 Mechanical Properties of Lightweight Foamed Concrete

Mechanical properties of lightweight foamed concrete is more related to the

samples size and shape, method of pore formation, direction of loading, age of

samples, characteristic of the ingredients were used and method of curing.

Documents

PERFORMANCE OF LIGHTWEIGHT FOAMED CONCRETE USING