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OPTIMUM MIX OF FOAMED CONCRETE BY USING DIFFERENT MATERIALS Kasrinawati Binti Sebeli Bachelor of Engineering with Honours (Civil Engineering) 2009

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OPTIMUM MIX OF FOAMED CONCRETE BY USING DIFFERENT MATERIALS

Kasrinawati Binti Sebeli

Bachelor of Engineering with Honours (Civil Engineering)

2009

UNIVERSITI MALAYSIA SARA W AK

BORANG PENGESAHAN STATUS TESIS

Judul: Optimum Mix of Foamed Concrete By Using Different Materials

SESI PENGAJIAN: 2008/2009

Saya KASRINA WATI BINTI SEBELI (HURUF BESAR)

mengaku membenarkan tesis * ini disimpan di Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dengan syarat-syarat kegunaan seperti berikut:

1. Tesis adalah hakmilik Universiti Malaysia Sarawak. 2. Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dibenarkan membuat salinan untuk

tujuan pengajian sahaja. 3. Membuat pendigitan untuk membangunkan Pangkalan Data Kandungan Tempatan. 4. Pusat Khidmat Maklumat Akademik, Universiti Malaysia Sarawak dibenarkan membuat salinan tesis ini

sebagai bahan pertukaran antara institusi pengajian tinggi. 5. * * Sila tandakan ( ~ ) di kotak yang berkenaan

DSULIT

D TERHAD

o TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972).

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasil badan di mana penyelidikan dijalankan).

Disahkan oleh

(TANDATANGAN PENULIS) (TANDATANGAN PENYELIA)

Alamat tetap: 268A, KG. TABUAN HILIR,

Tarikh:

CATATAN

JALAN SETIA RAJA, 93450 KUCHING Dr. Mohd Ibrahim Safawi Mohd Zin Nama Penyelia

6 APRIL 2009 Tarikh: 6 APRIL 2009

Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah, Sarjana dan Sarjana Muda. Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasalorganisasi berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu dikelaskan sebagai SULIT dan TERHAD.

The Following Final Year Project:

Title : Optimum Mix of Foamed Concrete by Using Different Materials

Author : Kasrinawati bt. Sebeli

Matrix Number : 14258

Was read and certified by:

Dr. Mohd Ibrahim Safawi Mohd Zin

Project Supervisors

Date

OPTIMUM MIX OF FOAMED CONCRETE BY USING DIFFERENT MATERIALS

KASRINAWATI BINTI SEBELI

This project is submitted to Faculty of Engineering,

University Malaysia Sarawak in partial fulfilment of the requirement for the

Degree of Bachelor of Engineering with Honours (Civil Engineering) 2009

For my beloved parent, Mr Sebeli andMdm SUi

My beloved siblings and dearest friends

Thanks for all your supports

ACKNOWLEDGEMENT

Bismillahhirrahmannirrahim.

In the name of Allah the Gracious and the Merciful.

First of all, I would like to take this opportunity to express my SIncere

gratitudes to all those who have contributes, supports and encourage me in my way

to complete this final year project. Without all of you, I will not be able to

accomplish this project successfully.

My deepest thanks and appreciation goes to my supervIsor, Dr. Mohd.

Ibrahim Safawi Bin Mohd. Zin for his guidance, motivation and encouragement. His

advices, suggestions and comments are gratefully acknowledged.

Sincere thanks also go to the Concrete Laboratory technician, Mr. Adha for

his guidance. Without his assists and helps, this project will not be a success.

Last but not least, my sincere appreciation goes to all my families. Thanks for

their sacrifice, continuous support and encouragement throughout the completion of

my final year project. A special thanks also goes to all my dearest friends for their

kindness, helps and supports.

ABSTRACT

Foamed Concrete is a special concrete which can be very useful in the construction

because it is lightweight and a self compacted concrete. It is necessary here and can

be cast easily into every corner of formwork especially for mass concreting. Many

researches have been done in overseas show that the foamed concrete can reduce

load in construction compared to normal construction. Materials used to produce

foamed concrete are cheap thus it will reduce the construction cost. In Malaysia

especially in Sarawak, foamed concrete is still new. Before it can be use in the

constructions, a lots of study need to be done on foamed concrete. The objective of

this project is to determine the optimum mix of foamed concrete using different

materials which are Fly Ash (FA), Silica Fume (SF) and Calcium Carbide (CC). In

this project, the mix of foamed concrete has been done on two conditions. First

condition is by replacing 50% cement and second condition is by replacing the sand.

Both conditions are done in two ratios 1: 1 and 1:2. Water to cement ratio is fixed 0.5

and the target wet density is 1000kg/m3. Two tests done are Flow Table Test and

Compressive Strength on 7 days and 28 days. The results from this project show

different materials replaced in the foamed concrete influence the performance and

quality of foamed concrete itself.

ii

ABSTRAK

Konkrit Busa adalah konkrit khas yang amat berguna dalam pembinaan kerana

sifatnya yang ring an dan boleh mampat sendiri. Konkrit Mampat Sendiri (SCC)

boleh dituang dengan senang ke dalam bucu acuan terutamanya untuk kerja konkrit

yang besar. Banyak kajian telah dijalankan di luar negara menunjukkan bahawa

Konkrit Busa dapat mengurangkan beban dalam pembinaan berbanding konkrit

biasa. Bahan yang digunakan untuk menghasilkan konkrit busa murah dan itu akan

mengurangkan kos pembinaan. Di Malaysia terutamanya di Sarawak, Konkrit Busa

adalah satu teknologi baru. Sebelum ia dapat digunakan dalam pembinaan, banyak

kajian perlu dijalankan ke atas konkrit tersebut. Objektif projek ini adalah untuk

mengenalpasti bancuhan optima Konkrit Busa dengan menggunakan bahan berlainan

iaitu Fly Ash (FA), Silica Fume (SF) dan Calcium Carbide (CC). Untuk projek ini,

bancuhan Konrit Busa telah dilakukan dalam dua keadaan. Keadaan yang pertama

adalah dengan menggantikan 50% kandungan simen dan keadaan kedua adalah

dengan menggantikan pasir di dalam bancuhan tersebut. Bancuhan untuk kedua-dua

keadaan ini telah menggunakan dua nisbah iaitu 1: 1 dan 1:2. Nisbah air dan cement

adalah tetap iaitu 0.5 dan anggaran ketumpatan adalah 1000kg/m3. Dua eksperimen

telah dilakukan iaitu Flow Table Test dan Kekuatan Mampatan pada 7 dan 28 hari.

Keputusan dari kajian ini menunjukkan bahan yang berlainan dalam bancuhan

mempengaruhi pre stasi dan kualiti Konkrit Busa itu sendiri.

iii

TABLE OF CONTENT

CONTENT PAGE

ACKNOWLEDGEMENT

ABSTRACT 11

ABSTRAK 111

T ABLE OF CONTENT IV

LIST OF TABLES IX

LIST OF FIGURES X

CHAPTER 1 INTRODUCTION

1.1 Background of Project 1

1.2 Objective of Study 5

1.3 Limitation/Scope of Study 5

1.4 Proj ect Outline 6

iv

CHAPTER 2 LITERATURE REVIEW

2.1 Properties of Foamed Concrete 7

2.2 Characteristic of Foamed Concrete 9

2.3 Foamed Concrete Mix Design 12

2.3.1 Water Demand of Mix Constituent 13

2.3.2 Mix Proportion for Foamed Concrete 13

2.4 Cement and Sand Replacing Materials 17

2.4.1 Fly Ash 17

2.4.2 Silica Fume 17

2.4.3 Calcium Carbide 19

CHAPTER 3 METHODOLOGY

3.1 General 21

3.2 Preparation and Casting of Foamed Concrete 22

3.3 Mixing Procedure 23

3.4 Cement Sand Ratio 24

3.5 Water Cement Ratio 24

3.6 Equipments 25

3.6. 1 Foam Generator 25

v

3.6.2 Air Compressor 26

3.6.3 Concrete Mixer 26

3.6.4 Mini Cone 27

3.6.5 Mortar Mixer 28

3.6.6 Moulds 28

3.7 Materials 29

3.7.1 Ordinary Portland Cements 29

3.7.2 Sand 30

3.7.3 Water 30

3.7.4 Foaming Agent 30

3.7.5 Fly Ash 31

3.7.6 Silica Fume 31

3.7.7 Calcium Carbide 32

3.8 Experimental Program 32

3.8.1 Condition 1 Cement to Sand ratio 1: 1 33

3.8.2 Condition 1 Cement to Sand ratio 1:2 34

3.8.3 Condition 2 Cement to Replacement Material ratio 1: 1 34

3.8.4 Condition 2 Cement to Replacement Material ratio 1:2 35

vi

3.9 Tests 35

3.9. 1 Workability 35

3.9.2 Strength 36

CHAPTER 4 RESULTS AND ANALYSIS

4.1 General 38

4.2 Mix Proportions 39

4.3 Physical Description of Foamed Concrete on Condition 1 40

4.4 Physical Description of Foamed Concrete on Condition 2 43

4.5 Flow Table Test 47

4.6 Compressive Strength Test 51

4.7 Summary 57

CHAPTER 5 CONCLUSIONS

5.1 General 58

5.2 Conclusions 58

5.3 Recommendations 60

5.4 Limitations 61

vii

REFERENCE 62

APPENDIX A 64

APPENDIXB 66

viii

LIST OF TABLES

TABLES PAGE

2.1 Typical Foamed Concrete Properties 7

2.2 Typical properties ofLCM foamed concrete 8

2.3 Fire resistance comparison test between

foamed concrete and vermiculite. 11

2.4 Mix proportions in m3 for the series of foamed concrete

investigated with W/C of 0.5 15

3.1 Condition 1 CIS 1: 1 33

3.2 Condition 1 CIS 1:2 34

3.3 Condition 2 (1: 1) 34

3.4 Condition 2 (1:2) 35

3.5 Programs on Compressive Strength Test 37

4.1 Mix Proportions on Condition 1 39

4.2 Mix Proportions on Condition 2 39

4.3 Flow Table Test Results on Condition 1 47

4.4 Flow Table Test Results on Condition 2 49

4.5 Compressive Strength Results on Condition 1 51

4.6 Compressive Strength Results on Condition 2 53

ix

LIST OF FIGURES

FIGURES PAGE

1.1 Foam Production 2

2.1 Example of foamed concrete 9

3.1 Foam Generator 25

3.2 Air Compressor 26

3.3 Concrete Mixer 27

3.4 Mini Cone for Flow Table Test 27

3.5 Mortar Mixer 28

3.6 100 x 100 Mould for mortar samples 29

3.7 Cement 29

3.8 Sand 30

3.9 Fly Ash 31

3.10 Silica Fume 31

3.11 Calcium Carbide 32

3.12 Flow Table Test 36

4.1 Cube made of Mix FA1 40

4.2 Cube made of Mix FA2 40

4.3 Cube made of Mix SF1 41

4.4 Cube made of Mix SF2 42

4.5 Cube made of Mix CC1 42

4.6 Cube made of Mix CC2 43

4.7 Surface texture of Mix F A3 44

x

4.8 Surface texture of Mix F A4 44

4.9 Cube made of Mix SF3 45

4.10 Cube made of Mix SF4 45

4.11 Cube made of Mix CC3 46

4.12 Cube made of Mix CC4 46

4.13 Bar chart of Flow Table Test on Condition 1 (1:1) 48

4.14 Bar chart of Flow Table Test on Condition 1 (1:2) 48

4.15 Bar chart of Flow Table Test on Condition 2 (1:1) 50

4.16 Bar chart of Flow Table Test on Condition 2 (1:2) 50

4.17 Graph of Compressive Strength on Condition 1 (1: 1) 52

4.18 Graph of Compressive Strength on Condition 1 (1:2) 52

4.19 Graph of Compressive Strength on Condition 2 (1: 1) 54

4.20 Graph of Compressive Strength on Condition 2 (1:2) 54

4.21 Graph of Compressive Strength of Foamed Concrete with Fly Ash 55

4.22 Graph of Compressive Strength of

Foamed Concrete with Silica Fume 56

4.23 Graph of Compressive Strength of

Foamed Concrete with Calcium Carbide 56

4.24 Compressive Strength of Foamed Concrete with different materials 57

xi

CHAPTERl

INTRODUCTION

1.1 BACKGROUND OF PROJECT

Foamed concrete is a lightweight concrete containing no aggregates, only

find sands, cement, water and foam. The product of cement, water and foam more

accurately describe as foamed mortar. The base mix or basic form of foamed

concrete is a blend of sand, cement and water. The pre-formed foam is a mixture of

foaming agent, water and air. The foaming agent can be either synthetic or protein

based. According to [1], as a rule of thumb a foamed concrete is described as having

an air content of more than 25% which distinguishes it from highly air entrained

materials.

The addition of the pre-formed foam into a base mix will increase the volume

of the mortar. But the preformed foam is very weightless so the mass of the foamed

mortar will have only little increasing but somehow it will maintain as base mix

1

mass. Because of that the density of the foamed mortar will be decreasing. With the

more foam added to base mix, the lighter the density will be.

The pre-formed foam can be divided onto two categories wet foam and dry

foam. Wet foam is produced by spraying a foaming agent and water over a fine

mesh. Usually we use synthetic foaming agent to produce wet foam. By spraying a

foaming agent cause a drop in pressure across the mesh and allowing air to be sucked

from atmosphere to equal the pressure. This equalization of pressure will be resulting

as foam similar in appearance to bubble bath foam. Normally, the bubble size range

from 2-Smm. The foam has a large 'loose' bubble structure. Although it is relatively

stable, it is not recommended for the production of low density foamed materials. It

is also not suitable for pumping long distance or pouring to any great depth. When

the pressure on material increases, the bubbles basically burst causing a decrease in

volume and this will increase the density.

Figure 1.1: Foam Production

2

Dry foam is produced by forcing a similar solution of foaming agent and

water through a series of high density and compressed air into a mixing chamber. By

forcing this pressurized air resulting into thick, tight foam, similar in appearance to

shaving foam. Typically the bubble size is less than 1mm in diameter and of an even

size. Dry foam is extremely stable and the properties are passed onto foamed

materials when the foam is blended with the base materials. This stability is

particularly important when the ratio of foam to base materials is greater than 50:50.

When the foams become the dominant of the mix, it has to retain the stability to

avoid collapse during the production. Dry foam can be pumped further, poured

deeper and produce better flow characteristics than wet foam.

The use of air entrained and foamed concrete has grown rapidly in recent

years than any other "special" concrete product. Two millenniums ago, the Romans

were making a primitive concrete mix consisting of small gravel and coarse sand mix

together with hot lime and water. It is discovered that by adding animal blood into

the mix will create small air bubbles making the mix more workable and durable.

Then they were adding horse hair to reduce shrinkage, similar like fibers which we

use today.

According to [1], obviously these very early air entrained concretes were

extremely basic with no control over air content. It was not until the early 1900's that

the manufacture of highly entrained materials began to be commercially explored,

with perhaps surprisingly Sweden being the pioneers behind it, based on the

workings of Axel Erikson. Doubtless the extreme weather experienced by this

3

country gave impetus to the development of an extremely thermally efficient

building material but this foresight remains today with Sweden still being one of the

biggest users of lightweight foamed concrete's.

Dependant on the application standard cement replacement, such as

pulverized fuel ash, PF A and ground granulated blast furnace slag, GGBS can be

used along with a range of fillers in addition to sand, such as chalk and crushed

concrete. The foam added to the base material must be capable of remaining stable

especially when the foam is the dominant which comprises more than 50% of the

mix. This usually occurs at around 1100kg/m3 density, with foamed mix below this

density must be manufactured and handle with care. The replacement of cement and

sand can be 100% replaced or varies according to the mix proportion that has been

design for the materials.

4

1.2 OBJECTIVE OF STUDY

i) To determine the workability and compressive strength of foamed concrete

using different materials.

ii) To find the optimum mix of foamed concrete using different materials on two

conditions; Condition 1 (cement replacement) and Condition 2 (sand

replacement).

iii) To find the optimum mix of foamed concrete using different materials on two

cement to sand ratios which are 1: 1 and 1:2.

1.3 LIMITATIONS/ SCOPE OF STUDY

i) The foamed concrete will be produce in two mix conditions with the sand and

without sand.

ii) The foamed concrete will be produced in two cement to sand ratio which are

1: 1 and 1:2 for each material replacing the cement.

iii) On Condition 1, 50% of cement will be replaced.

iv) On Condition 2, 100% sand will be replaced.

v) The water to cement ratio is 0.50 for all mixes.

vi) The required density for the foamed concrete is 1 000kg/m3.

5

1.4 PROJECT OUTLINE

This report contains of five chapters. First chapter is the introduction, second

chapter is the literature review, third chapter is the methodology, and fourth chapter

is the results and analysis. The final fifth chapter is the conclusions and

recommendations.

1.4.1 Chapter 1: Introduction

This chapter is the brief introduction of the project, the objectives and the

scope and limitation of the project.

1.4.2 Chapter 2: Literature Review

This chapter is the theoretical of the properties of foamed concrete and a brief

explanation of different material that will be use to replace the cement in the

foamed concrete.

1.4.3 Chapter 3: Methodology

This chapter is the view of experimental program that will be use in this study

such as the method, equipments, materials, the procedure and the testing that

will be done to achieve the objective of this study.

1.4.4 Chapter 4: Results and Analysis

This chapter will be the results achieve from the experiment that have been

done and the analysis of the result itself.

1.4.5 Chapter 5: Conclusions

This chapter is the conclusions of the study that have been done and any

recommendations for improving the study in the future.

6

CHAPTER 2

LITERATURE REVIEW

2.1 PROPERTIES OF FOAMED CONCRETE

Fresh foam concrete looks like a thin grey mousse or milkshake. Hardened

foam concrete is comparable in appearance to autoc1aved gas concrete products such

as a celcon or thermalite block. Foam concrete is cement based slurry in which

stable, homogeneous foam is mechanically blended, either by mixing or by injecting.

Typical foam concrete properties are summarized in Table 2.1 below.

Table 2.1: Typical foamed concrete properties.

DRY COMPRESSIVE MODULUS DRYING DENSITY STRENGTH ELASTICITY SHRINKAGE

Kg/m3 N/mm2 kN/mm2 % 600 1.0-1.5 1.0-1.5 0.22-0.25

800 1.5-2.0 2.0-2.5 0.20-0.22

1000 2.5-3.0 2.5-3.0 0.18-0.15

1200 4.5-5.5 3.5-4.0 0.11-0.09

1400 6.0-8.0 5.0-6.0 0.09-0.07

1600 7.5-10.0 10.0-12.0 0.07-0.06

7

According to [5], specification for controlled density foamed concrete

products have been prepared for the ready mix concrete industry in Malaysia

based on typical properties of foamed concrete (Table 2.2) made with

Lightweight Concrete Methods (LCM) foaming agent. The drying shrinkage of

such foamed concrete is less than 0.09% for dry density more than 1500kg/m3.

The average coefficient of water permeability determined in accordance with

ISOIDIS 7031 is in order of 10-10 rnIs for foamed concrete of dry density between

1500kg/m3 and 1600kg/m3. This test was conducted with German Water

permeability Test Rig on two surfaces of two foamed concrete cubes to obtain the

average.

Table 2.2: Typical properties of LCMfoamed concrete.

Cement kg/mJ 1 1

MIX Fine Sand kg 2 2

PROPORTIONS WaterlBinder ratio 0.45 0.5

FoamlBinder ratio 0.65 0.7

DRY DENSITY kg/mJ 1500 1600

COMPRESSIVE 7-days 5-6 7-8

STRENGTH

N/mm2 28-days 7-8 8 - 10

8