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OIL CLINKER< 1 rrrrnrrn1 0000073616
RETE USING PALM
PLACEMENT
MUHAMMAD JAHIDUDDIN BIN ABU JAMAL
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
MAY 2011
v
ABSTRACT
Palm oil industry is one of the most important Argo industries in Malaysia. Anually,
large amounts of solid waste of palm oil residue are not utilized as a functional
wastage and affect the environmental problems. Through public concerns and
research effort, the agro waste by-product materials have potential to be utilized as
construction material to replace conventional sand. In this study, the effectiveness of
agro waste clinker by-product namely palm oil clinker crushed (POCC) was
developed as an alternative material to replace the sand. In this present study, the
effect of using different percentage of POCC to lightweight foamed concrete (L WC)
due to compressive strength and elastic modulus were investigate. Four series of mix
formulation L WC were prepared comprise of 0%, 5%, 10% and 15% as sand
replacement from the total weight of sand. All the L WC specimens were cured in air
curing for different curing ages namely 7, 28 and 60 days. The result revealed that by
replacing the sand with POCC to L WC were significantly effect the compressive
strength. The compressive strength also improved due to increasing the curing days.
On the other hand, the modulus of elastic was improved significantly by increasing
the percentage of POCC due to different curing days. It is noted that the optimum
mix design to produce LWC-POCC was obtained by using 10% of POCC as sand
replacement.
vi
ABSTRAK
Industri minyak sawit adalah salah satu industri pertanian paling penting di Malaysia.
Setiap tahun, sejumlah besar sisa pepejal kelapa sawit tidak digunakan sebagai bahan
pembaziran yang boleh digunapakai dan akan mempengaruhi masalah alam sekitar.
Melalui keprihatinan orang awam dan juga usaha kajian, pembuangan sisa pertanian
ini mempunyai potensi untuk dimanfaatkan sebagai bahan dalam pembinaan untuk
menggantikan pasir konvensional. Dalam kajian ini, keberkesanan k.linker sisa
pepejal pertanian yang dinamakan k.linker kelapa sawit hancur (POCC) dibangunkan
sebagai bahan alternatif untuk menggantikan pasir. Dalam kajian ini, pengaruh
penggunaan peratusan POCC yang berbeza untuk konkrit ringan berongga (L WC)
diuji terhadap ujian kekuatan mampatan dan modulus keanjalan disiasat. Empat siri
formulasi campuran LWC disediakan terdiri dari 0%, 5%, 10% dan 15% sebagai
pengganti pasir dari berat keseluruhan pasir. Semua sampel L WC diawetkan di udara
pada usia berbeza iaitu 7, 28 dan 60 hari. Keputusan kajian menunjukkan bahawa
dengan menggantikan pasir dengan POCC untuk L WC secara signifikasinya
mempengaruhi kekuatan mampatan. Kekuatan mampatan juga meningkat kerana
peningkatan hari pengawetan yang berbeza. Disamping itu, didapati modulus
keanjalan meningkat secara signifikan dengan meningkatkan peratusan POCC dan
berbezaan hari pengawetan. Didapati campuran optimum untuk menghasilkan L WC
POCC diperolehi dengan menggunakan 10% dari POCC sebagai pengganti pasir.
CHAPTER
CHAPTERl
CHAPTER2
TABLE OF CONTENTS
ITEM TITLE DECLARATION ACKNOWLEDGEMENT ABSTRACT ABSTRAK TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF ABBREVIATIONS
INTRODUCTION 1.1 Background of Study 1.2 Objectives of Study
1.3 Problem Statement 1.4 Scope of Study
LITERATURE REVIEW
vii
PAGE
lV
v Vl
vii x
xii XIV
4 4
5
2.1 Introduction 7 2.2 Lightweight Foamed Concrete 9
2.2.1 Definition of Lightweight Foamed Concrete IO 2.2.2 Historical of Lightweight Foamed Concrete 11 2.2.3 Advantages of Lightweight Foamed Concrete 11 2.2.4 Weight Reduction 12 2.2.5 Thermal Insulation 12 2.2.6 High Durability 13
2.3 Lightweight Foamed Concrete Properties 13 2.3.l Mechanical Properties of Lightweight Foamed
Concrete 14 2.3.2 Physical Properties of Lightweight Foamed
Concrete 2.3.3 Durability
15 15
viii
2.3.4 Water Absorption and Capillarity 16 2.3.5 Thermal Properties 16
2.4 Application of Lightweight Foamed Concrete 17 2.5 Compressive Strength of Lightweight Foamed
Concrete 19 2.6 Factor Affecting the Compressive Strength of
Lightweight Foam Concrete 19 2.6.1 Different Density of Lightweight Foamed
Concrete 20 2.6.2 Different Curing Day 20
2.7 Modulus of Elasticity of Lightweight Foamed Concrete 21 2.8 Palm Oil Clinker Crushed (POCC) 22
2.8.l History of Palm Oil Clinker Crushed (POCC) 23 2.8.2 Definition of Palm Oil Clinker Crushed (POCC) 23 2.8.3 Properties of Palm Oil Clinker Crushed (POCC) 24
2.9 Density/ Unit Weight 24 2.10 Applications of Palm Oil Clinker Crushed (POCC) 24
CHAPTER3 METHODOLOGY 3.1 Introduction 26 3.2 Materials Selection 28
3.2.1 Cement 28 3.2.2 Palm Oil Clinker Crushed 29 3.2.3 Water 31 3.2.4 Fine Aggregate (Sand) 31 3.2.5 Foam Agent 32
3.3 Preparation of Specimen Lightweight Foamed Concrete 33 3.3.l Specimen Preparation 34 3.3.2 Determine Weight of Raw Materials 36
3.4 Lightweight Foamed Concrete Mix Design 36 3.5 Curing Method 37 3.6 Sieve Analysis Testing 38 3.7 Compressive Strength 39
3.7.l Compressive Strength Testing Procedure 39 3.8 Modulus of Elasticity 41
ix
CHAPTER 4 RESULT AND DISCUSSION 4.1 Introduction 42 4.2 Effect on Different Percentage of Palm Oil Clinker
Crushed to Lightweight Foamed Concrete Due to Compressive Strength 43
4.3 Effect on Different Curing Ages of Palm Oil Clinker Crushed o Lightweight Foamed Concrete Due to Compressive Strength 49
4.4 Effect on Different Percentage of Palm Oil Clinker Crushed to Lightweight Foamed Concrete Due to Modulus of Elasticity 55
4.5 Effect on Different Curing Ages of Palm Oil Clinker Crushed to Lightweight Foamed Concrete Due to Modulus of Elasticity 57
CHAPTER 5 CONCLUSION AND RECOMMENDATION 5.1 5.2 5.3
Introduction Conclusion Recommendation
REFERENCES
59 60 61
62
xi
LIST OF TABLES
TABLE NO TITLE PAGE
1.1 Numbers of L WC-POCC Specimens due to Compressive
Strength 6
1.2 Numbers ofLWC-POCC Specimens due to Modulus of
Elasticity 6
2.1 Typical Properties of Lightweight Foamed Concrete 15
2.2 Lists of the Various Density of Foam Concrete Due to Its
Applications 18
3.1 Numbers ofLWC-POCC with Density of 1400 kg/m3 35
3.2 Weight of Raw Materials for LWC in lm3 36
4.1 Result on Compressive Strength of L WC with 0% of
POCC 43
4.2 Result on Compressive Strength of L WC with 5% of
POCC 44
4.3 Result on Compressive Strength of L WC with l 0% of
POCC 45
4.4 Result on Compressive Strength of L WC with 15% of
POCC 46
4.5 Summary Result on Compressive Strength for L WC-
POCC at Different Percentage of POCC 48
4.6 Result on Compressive Strength at 7 Days of Curing Age 49
4.7 Result on Compressive Strength at 28 Days of Curing Age 51
4.8 Result on Compressive Strength at 60 Days of Curing Age 52
4.9 Summary Result on Compressive Strength of L WC-POCC
at Different Curing Ages
4.10
4.1 1
Summary Result on Modulus of Elasticity for L WC-POCC
at Different Percentages of POCC
Summary Result on Modulus of Elasticity for L WC-POCC
at Different Curing Ages
xii
54
56
58
xii
LIST OF FIGURES
FIGURE NO TITLE PAGE
1.1 Dimension of Standard Specimern 6
3.1 Experimental Process Flow 27
3.2 Ordinary Portland Cement (OPC) 28
3.3 Production of Palm Oil Clinker Crushed (POCC) 30
3.4 Water 31
3.5 Sand 32
3.6 Protein Foams tend to have an off white colour 33
3.7 Steel Mould of L WC Cube 35
3.8 Steel Mould of L WC Cylinder 35
3.9 Air Curing 37
3.10 Analysis Test Equipment 38
3.11 Compressive Strength Test Machine 40
3.12 Modulus of Elasticity Test Machine 41
4.1 Compressive Strength of L WC with 0% of POCC 43
4.2 Compressive Strength of L WC with 5% of POCC 44
4.3 Compressive Strength ofL WC with 10% of POCC 45
4.4 Compressive Strength of L WC with 15% of POCC 46
4.5 Summary Result on Compressive Strength for L WC-POCC
at Different Percentage of POCC 48
xiii
4.6 Compressive Strength ofLWC-POCC at 7 Days of Curing
Ages 50
4.7 Compressive Strength of L WC-POCC at 28 Days of Curing
Ages 51
4.8 Compressive Strength ofLWC-POCC at 60 Days of Curing
Ages 52
4.9 Summary Result on Compressive Strength ofLWC-POCC
at Different Curing Ages 55
4.10 Summary Result on Modulus of Elastic for L WC -POCC at
Different Percentages of POCC 57
4.11 Summary Result on Modulus of Elastic for L WC -POCC at
Different Curing Ages 58
ASTM
BS
LWC
MOE
FKASA
OPC
POC
POCC
W/C
xv
LIST OF ABBREVIATIONS
American Society for testing and Materials
British Standard
Lightweight Concrete
Modulus of Elasticity
Fakulti Kejuruteraan Awam dan Sumber Alam
Ordinary Portland Cement
Palm Oil Clinker
Palm Oil Clinker Crushed
Water-Cement
CHAPTER!
INTRODUCTION
1.1 Background of Study
Generally, conventional concrete is produced in the density ranges of
2200 kg/m3 to 2600 kg/m3. Last decade has seen great strides in the realm of concrete
density and fantastic compressive strengths. The strength concrete is seriously affected
by the degree of it compaction, consistence of the mix of that concrete can be
transported, placed and finished sufficiently easily and without segregation
(Neville, 1993).
Since the government of Malaysia had a vision and mission about the green
buildings construction where it is the practice of creating structures and using processes
that are environmentally responsible and resource-efficient throughout a building's life
cycle from sitting to design, construction, operation, maintenance, renovation, and
deconstruction. This practice expands and complements the classical building design
2
concerns of economy, utility, durability, and comfort. The reason why government of
Malaysia concern about the green building because it is designed to save energy and
resources, recycle materials and minimize the emission of toxic substances throughout
its life cycle. SMART tunnel is the one of the mega project was build according to
Industry Building System (IBS).
Even though conventional concrete is a remarkable building material, it has
disadvantages such as not flexible or heat insulating enough to be used independently
for building structure components and extremely heavy limiting for use as building
structure components. In addition to the lack of flexibility and lightweight weakness of
insulating properties, conventional concrete is further not adeqmte for use as building
element.
Since the conventional concrete has problems and disadvantages, thtre are an
alternative to improve the existing conventional concrete due to the density. The
development of lightweight foamed concrete (L WC) were introduced. According to the
BS 8110: Part 2: 1985 it was defined that L WC begin in the density range of less than
conventional concrete which is 2000 kg/m3or less. Decreasing the weight and density
produces significant changes which improves many properties of concrete, both in
placement and applications.
L WC can be defined as a combination of extremely lightweight foamed
materials containing cement, water and foam agent. It can be produced at the
construction site similarly to ordinary concrete. The difference between conventional
concrete and L WC is it does not use coarse aggregate, but µ-e-formed foam. Aldridge
(2005) revealed that foamed concrete is a type of concrete having an air content of more
than 25% which distinguished it from highly air entertained materials. L WC has many
advantages such as it could posses excellent in workability, good thermal, does mt
3
decompose and it is durable as rock. In addition, Narayanan and Ramamurthy (2000)
noted that the most benefits of L WC are reducing the dead weight of structure which
economizes the design of supporting structure. However L WC has disadvantages in
terms of the lower density ranges L WC does not develop the compressive strength of
plain concrete.
As an alternative to solve the problems, a various research were developed to
increase the compressive and performance of L WC. One of the researches was
introduced are replacing of sandby using product by waste material. This method is the
most suitable because it does not create any pollution. From the by product by waste
material that not being use or recycled it is better to reuse it as a replacement in
construction materials.
In this study, introduce a product by waste material from palm oil plantation
namely palm oil clinker crushed (POCC) in the mixing of L WC as a sand replacement.
This material is chosen because in Malaysia it is stated that the total of wase is more
than 30 millions tone per annum which generate more than 8 millions tore of empty
fruit bunch (Fauziah, 2005).
This study is important to determine the performance of L WC by adding various
percentages of POCC as sand replacement by weight of send and determine compressive
strength of it and determine the effect of using different percentages of L WC as sand
replacement to lightweight foamed concrete.
4
1.2 Objectives of Study
The objectives ofthis study are:
1. To determine the compressive strength of lightweight foamed concrete with
different percentage of palm oil clinker crushed (LWC-POCC) as sand
replacement.
11. To determine the modulus of elasticity of lightweight foamed concrete with
different percentage of palm oil clinker crushed (L WC-POCC) as sand
replacement.
iii. To determine the effect of using different percentage of POCC as sand
replacement to L WC.
1.3 Problem Statement
Nowadays world has been witnesses a lot of revolution in the using of L WC for
the construction industry. Many researches had done to find any materials that can be
used to replace the raw material in L WC. Basically, the main ingredients of L WC are
cement, foam agent, fine aggregates (sand) and water.
Sand was the key ingredient in L WC provision because it demand in rising
construction field, in the course of time it will decline and might be due one time later it
will completely been used. Besides that, activity sand mining could also cause
ecological system in disturbed rivers and mountains.
5
As such to overcome this, a study reduce sand use in L WC should be conducted.
Through this problem, one solution suggested is the use of palm oil plantation wastage
namely POCC as replacement with a portion by total weight of sand. Study the optimum
percentage composition of POCC can replace sand would be made for overcome this
problem.
1.4 Scope of Study
In this study, the lightweight foamed concrete (L WC) were produced to
investigation the compressive strength and modulus of elasticity using different
percentage of palm oil clinker crushed (POCC) as sand replacement. The percentages of
POCC as sand replacement by total weight of sand are 0%, 5%, I 0% and I 5%. POCC
were mixed with cement, fine aggregate, foam agent and water The design of density
for L WC must be obtained is I 400 kg/m3 with mix proportion ratio 2: I: I comprises of
cement to sand to water ratio 0.5. Otherwise, the L WC without sand replacement were
design as a control mix.
There were 36 cubes L WC were prepared to be test on compressive strength and
36 cylinders are prepared to be test on modulus of elasticity. Minimum three samples
were prepare for each parameter arrl the sample must accordance to BS: I 881: Part I 08:
1983 for 0%, 5%, 10% and 15%. All the specimens were tested after expose to air
curing at 7, 28, 60 days. The number of sample prepared as shown in Tables I. I and 1.2.
In addition, the dimension for cubes and cylinder is 150 mm x 150 mm x I50 mm and
150 mm x 300 mm respectively as shown in Figure I. I. 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: I881: Part I 16:
1983.
6
Table 1.1 Numbers of L WC-POCC Specimens due to Compressive Strength
Mix proportion Percentage of
Numbers of sample (cubes) Mix Design
Cement: sand: POCC (%) 7 days 28 days 60 days
water
(Control) 3 3 3
1400 kg/m3 2: 1 :1 5 3 3 3 10 3 3 3 15 3 3 3
Table 1.2 Numbers ofL WC-POCC Specimens due to Modulus of Elasticity
Mix proportion Percentage of
Numbers of sample (cylinder)
Mix Design Cement: sand: POCC(o/o)
7 days 28 days 60 days water
(Control) 3 3 3
1400 kg/m3 2: 1 :1 5 3 3 3 10 3 3 3 15 3 3 3
150mm
;/_I_< __ ~>I 300mm
a) Cube specimen b) Cylinder Specimen
Figure 1.1: Dimension of Standard Specimens
CHAPTER2
LITERATURE REVIEW
2.1 Introduction
Lightweight foamed concrete (L WC) 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 L WC. Foaming agents can be synthetic based or protein based.
The used of L WC offer many benefits and advantageous particularly fast
completion and easy application compared to other materials such as steel and timber.
L WC is characterized by its low compressive strength and high insulation against heat
and sound. The compressive strength and other functional properties of L WC are greatly
influenced by the amount of air content introduced by foaming agents.
8
The application of L WC 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 L WC panels and units. Very low density L WC can be used as thermal and
sound insulation panels, filtering media and floating blocks for fishery purposes.
This is due to the major problem that exists on usage of conventional concrete
are extremely heavy limiting for use as building structure components. Many
researchers try to produce new materials that are lower density but in the same time
could posses the same strength of the existing conventional concrete. The production of
this material could be ease to construction especia11y for Industry Building System (JBS)
requirements since it would be a great advantage to pr&cast systems (Shaari, 2004).
Thus the production of lightweight foamed concrete reinforced with palm oil clinker
crushed (L WC-POCC) is one of the alternative way to improve the existing
conventional concrete. Reinforcing the L WC-POCC may be used to help resist
compressive forces and improve dynamic properties.
On the other hands, L WC offers many benefits including reducing the dead
weight of a structure which economizes the design of supporting stnctures including the
foundation and walls of lower floors. Alex (2000) suggested that with appropriate mixed
design, a range of L WC with densities ranging from 300 kg/m3 to 1600 kg;m3 can be
produced. Besides that strength of L WC is mainly dependent on the amount of sand
while density is dependent on the amount of foam introduced (Hamidah et al, 2003).
Other parameters that affecting the strength of L WC are sand cement ratios, water -
cement ratios, curing regimes, types of sand and particle distribution of sand.
9
Basically, a foamed concrete that has lower density, the amount of sand that
could be incorporated is also limited due to the problems related to mix segregation and
stability. The amount of sand in foamed concrete requires compressive optimiza1ion to
ensure production of a sufficiently strong mix for the intended purposes without
sacrificing both the economics of the production and the practically in the mixing and
placing of such concrete (Hamidah et al., 2003).
Significantly, L WC is a good alternative to prevent this problem in construction.
Even though L WC is a good alternative, in the other side L WC also faces some
problems like conventional concrete that is insufficient water can cause lack of cohesion
between particles, thus loss in strength of L WC. Likewise too much water can cause
cement to run off aggregates to form laitance layers, subseqiently weakens in strength
(Kamsiah et al., 2007).
Due to the problem faced by L WC, the best solution is using palm oil clinker
crushed (POCC). The density of conventional concrete is produces in the ranges of
2200 kg/m3 to 2600 kg/m3 .Conventional concrete have many problems due to the
density (Gambhir, 1986). In this present chapter, the reviews ofLWC were presented.
2.2 Lightweight Foamed Concrete
Generally, lightweight foam concrete (L WC) can be defined as a combination of
extremely lightweight foam concrete materials containing cement, water and foam
agent. It can be produced at the construction site similarly to ordinary concrete.
10
L WC can be produced by adding a pre-foamed agent to cement base mortar.
Foamed concrete is one type of lightweight concrete that has an air content of more than
25%. The air will be introduced into a mortar or concrete mix using two principles
method.
Furthermore, the first stage is preformed foam from a foam generator can be mix
with other constituent in a higher- shear mixer. Decreasing the weight and density
produces a significant change which improves many properties of foam concrete, both
in placement and application (Alexander, 1977). The definition, history, properties and
applications and development of L WC were discussed in this present section.
2.2.1 Definition of Lightweight Foamed Concrete
Aldridge (2005) stated that in basic form concrete is a blend of sand, cement and
water (the base mix) and pre-formed foam, which in itself is a mixture of foaming agent,
water and air. The foam concrete partially combination of a cement.based mortar mixed
with at least 20 % by volume air (Jones et al. 1993). Furthermore, John August (1997)
noted that the very lightest density mixes which is 300 kg/m3 to 900 kg/m3 are often
made using foam in the absence aggregates. According to BS 8110: Part 2 (1985), the
foamed concrete density is begins in the range of 2000 kg/m3 or less than conventional
concrete.
11
2.2.2 ffistorical of Lightweight Foamed Concrete
Foamed Concrete was first developed in Stockholm, Sweden in the early 1900's.
The original material was known as "gas concrete" to be used in producing heat.
insulated building materials. The gas concrete is now known as cellular concrete,
foamed concrete, aerated concrete and autoclaved cellular concrete. Generally, the
properties of foam concrete can be indicated by doing laboratory testing.
The Expanded Clay and Slate Institute proved that most of the bridges appeared
to be in good condition. According to Diona et al., (1994), it was found that in Japan
LWC had been used since 1964 as a railway station platform. Even though some cracks
were reported, but these posed no structure problems. A second structure comprising
both L WC and normal concrete which had been in sea water for 13 years was examined
for salt penetration. In the late 1980's and 1990's, the foamed concrete was carried out
in Netherland for the research development (Van, 1991 ).
2.2.3 Advantages of Lightweight Foamed Concrete
Lightweight foamed concrete (L WC) physical properties are determined by
various mix designs of cements, palm oil clinker crushed, fines aggregates and volumes
of entrained foam. Generally L WC has many advantages compared to conventional
concrete such as light, doesn't settle, excellent load spreading and requires no
compaction. However, the biggest advantages is the fact that it can be produced right on
the spot of construction and be casted according to necessary shapes by pumping
straight to where it is required (Alex, 2000). In addition, the L WC also offers the
advantages such as thermal insulation and high durability.
12
2.2.4 Weight Reduction
Lightweight foamed concrete (L WC) density ranges from 250 kg/m3 to
1800 kglm3, as compared to 2400 kg/m3 for conventional concrete. Therefore, the
weight of structure built of foam concrete would undoubtedly be reduced significantly
thus, requiring less structure steel reinforcement and smaller foundations (Alex, 2000).
2.2.5 Thermal Insulation
Thermal insulation of concrete is important since it could determine the strength
to thermal for the concrete itself. A thermal insulation property is described as its ability
to resist flow of heat and is given as k value. Lightweight foamed concrete (L WC) with
a density of 1200 kg/m3, for instance, can produce a monolithic wall five times thinner,
requires ten times less raw material (by weight) and possesses five time more superior
thermal insulation property compared to that of conventional concrete. The amplitude
ratio and phase-displacement of a thick 150 mm thick of wall with a density of
1100 kg/m3 causes the outside temperature of a building to take between 10-12 hours to
reach the inside. Such a duration, which is much longer than that of conventional
concrete wall, results in a more energy-efficient enclosure. A study by Aldridge (2005)
stated that a typical sand cement screed would have a k value of 1.8 W/mk which
compares to 0.3 W/mk for 1000 kglm3 density foam concrete, making the L WC six
times more thermally efficient.
13
2.2.6 High Durability
Generally, the durability of lightweight foamed concrete (L WC) is as good as
normal concrete. Studies by Amiri et al., ( 1994) showed that L WC incorporating
lightweight aggregate has better chemical resistance compared to that of normal
concrete. It is shown that L WC containing air pores of diameter ranging of from 30 µm
to 50 µm have shown better resistance to freeze-thaw than that of normal concrete.
In addition, Amiri et al., (1944) indicated that L WC performs equally well under
cryogenic conditions such as for the storage of liquid gases due to its low penetrability.
Lightweight aggregate concrete also posses higher strain capacity which results in
greater crack resistance. It is worth nothing that the stated properties are enhanced at
low temperatures.
2.3 Lightweight Foamed Concrete Properties
In order to evaluate the relations between the physical properties arrl the ..
structural properties of lightweight foamed concrete (L WC) these properties have to be
identified. Kearsley, (1999) stated that a target casting density is determined and dry
density of the mixture is the most important factor affecting the properties of the mixture
when undertaking the design of a L WC mixture. The density is an important physical
property that has to be investigated. According to Kearsley (1990) noted that porosity,
ash I cement ratio, and age are also variables, which will influence the structural
characteristic ofL WC.