investigaton into an optimum mix proportion for
TRANSCRIPT
INVESTIGATON INTO AN OPTIMUM MIX PROPORTION FOR FOAMED CONCRETE WITH HIGH STABILITY IN
WATER
CH AN KW( )K KN': \NG
This project is submitted to Faculty of Engineering,
l'niversity ! Malaysia Sarawak in partial fulfilment of the requirement fiºr the
degree of Bachelor of Fngineering with I lonours (('i\ it Engineering) 2009
TO mº" hrlui"rcl parents and cherished /rirnclc
ACKNOWLEDGEMENT
First and foremost. the author would like to express his sincere thankfulness to Dr.
Mohammad Ibrahim Safawi Mohd Zain for his numerous advice and guidelines in
making this project success.
Acknowledgement also tbrwardcd to the staffs and technician in l1NIMAS Civil
Engineering Laboratory for their help and support in making this project success.
And also thanks to his course mate and friend for sharing their view, advice and their
physical strength in this project.
Finally. the author would like to thank to whom may directly or indirectly contribute
to the success ofthis project.
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ABSTRAK
Konkrit Bcrongga merupakan sejenis konkrit ringan yang mengandungi lebih
daripada 20 peratus udara dalam isipadunya. Hari ini, konkrit jenis demikian telah
digunakan secara mcluas dalam industri pcmhinaan. Konkrit hcrongga telah
digunakan secara meluas dalam kerja-kcrja mencmhus ruangan hcsar pada tapak
pembinaan, pcmbinaan Struktur ringan, bahan pcmhinaan kalis api, hunyi dan
sehagainya. Kchaikan konkrit berongga adalah sitätnya yang kctumpatan rcndah,
keholehaliran tinggi dan keupayaan diri untuk mernampat. Projek in adalah untuk
mcngkaji kcbolehgunaan konkrit berongga dalarn rnereka hcntuk laluan pejalan kaki
di atas tanah gamhut. Keholehapungan konkrit berongga telah diuji di atas air dcngan
muatan. Keputusan mcnunjukkan konkrit herongga dapat tapung atas air samhil
dapat mcnampung seYiikit muatan di atasnya.
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ABSTRACT
Foamed concrete is a kind of lightweight concrete that contain more that 20 % of air
in volume. This kind of concrete had been widely used in the construction industry
nowadays. Foamed concrete are widely use in high volume void fillings,
constructing lightweight structure, fire proofing material, sound proofing material
and etc. The advantages of foamed concrete are its low density, high flowahility,
self leveling and self=compacting. This project will present the applicability in using
foamed concrete to design pedestrian walkway on peat soil. The floatahility of
foamed concrete was tested in water with loading. The result shown that famed
concrete float in water and still he able to sustain some loading.
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Table of Content
Acknowledgement
Abstrak
Abstract
Table of Content
List of Table
List of Figure
Chapter 1 INTRODUCTION
1.1 General
1.2 Project Objectives
1.3 Design Concept
1.4 Scope of Study
1.5 Project Outlines
Chapter 2 I. ITF: RATI'RE REVIEW
2.1 (; rneral
Foamcd Concrete
'. '. I [)o-eloPmcnt
2.2.2 Characteristic
_'. '.? Forming Agent
2.2.4 Production
Pages
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3.5 Waxing Procedure 45
3.6 Experimental Test 46
3.6.1 Compressive Strength Test 46
3.6.2 Floatability and Settlement Test 47
3.7 Difficulties Faced in Project 48
3.7.1 Workability of the Foamed Concrete 48
3.7.2 Measurement of the Foam Quantity 48
3.7.3 Vanes in Density an Floatability of Samples
Chapter 4 RESULT AND ANALYSIS
4.1 General 50
4.2 Compressive Strength cif' Foamed Concrete 50
4.2.1 Result and Analysis cif the Compressive
Strength Test
4.2 .2 Discussion of the Result
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4.3 Floatahility Test 54
4.3.1 Result and Analysis ofthe Floating Test 54
4.3.2 Discussion of the Result 58
4.4 Loading Sustainahility Test 1 (()n Water) 60
4.4.1 Result and Analysis cif' Loading 'l'est 1 60
4.4.2 Discussion of Loading 'Fest I 63
4.5 Loading Sustainahility Trst 2 (On Water) 64
4.5.1 Result and Analysis cif' Loading 'l'est 2 64
4.5.2 Discussion of' Loacfing Test 2 69
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4.6 Loading Sustainability Test 3 (On Sand) 69
4.6.1 Result and Analysis of Loading Test 3 69
4.6.2 Discussion of Loading Tcst 3 70
Chapter 5 CONCLUSION AND RECOMMENDATION 72
5.1 Conclusion 72
5.2 Recommendation 73
BIBLIOGRAPHY- REFERENCES 74
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LIST OF TABLES
Table
2.1 Typical properties of foamed concrete
2.2 Comparison of thermal conductivity resistance
between foamed concrete and other materials
3.1 Suggested mix proportion carryout on this study
4.1 Density and compressive strength result for foam
concrete
4.2 Floating duration and properties of the cube samples
4.3 Comparison fior samples of'diflcrent w/c under target
density = 800 kg m`
4.4 Comparison fir samples of dificrent density under w/c
0.6
4.5 Result from Loading Test 2
4.6 Result from Loading Test 3
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LIST OF FIGURE
Figure Pages
2.1 Thermal conductivity versus densities of foamed
concrete
2.2 Exterior rims and arches (left) and intricate column
head produced using foamed concrete
2.3 Foamed concrete used as underlay and slab thickening
for airport project in Malaysia
2.4 Tunnel filing using foamed concrete in progress
2.5 Diagram showing the how the principle of equilibrium
works
2.6 Production of fly ash in a dry-bottom utility boiler with
electrostatic predicator
2.7 Pouring framed concrete into the hike path
2.8 Bike path was finish with asphalt after the foamed
concrete dry
2.9 Leveling of the tbamed concrete
3.1 Concrete mixer used fir the mixing
3.2 Foam generator (left) and air compressor (right)
3.3 1 UUx I OOx 100 mm site steel mould
3.4 Material required in producing foam dl concrete
3.5 Portland cement (left) and fly ash (right) use in the mix
3.6 MFV('O Fix SLF 30 firming agent
3.7 Timeline of foanudl concrete mixing process
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3.8 Curing in process
3.9 Process of waxing
3.10 Foamed concrete after waxing
3.11 Compressive strength test
3.12 Sample was tested for it floatability and loading
sustainability
4.1 Comparison of 7 days strength and 28 days strength
4.2 Cubes sample XI after curing for 7 days
4.3 Cube sample been crushed under compressive test
machine
4.4 Crushed cube sample from the test
4.5 Floating Duration of the cube samples
4.6 Cube sample FC606-B
4.7 Cube sample FC805-C
4.8 Cube sample FC606-E
4.9 Cube samples FC606-B floating on water
4.10 Companng void size between FC806-A (left) and
FC805-C (right)
4.11 Comparison for samples of different w%c under target
density 80l) kg ni'
4.12 Comparison firr samples of different density under w'e
0.6
4.13 Sample F('806-A2 hefirre adding load (left) and after
adding load (right)
4.14 Sample FC606-131 (without waxing) hefirre adding load
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(left) and after adding load (right)
4.15 Samples FC606-B3 (with waxing) before adding load
(left) and after adding load (right)
4.16 Graph show Cumulative Loading (g) versus Increment
of Water Level (mm)
4.17 Chart show maximum loading sustained by each target
density
4.18 Samples (900 kg/m ` on the left and 800kg/m ` on the
right) floating on water before test
4.19 Initial water level hetbrc test
4.20 Cube sample and water level during test
4.21 Cube sample after test and final water level
4.22 Graph show Cumulative Settlement (mm) versus
Loading Sustained (N)
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CHAPTER 1
INTRODUCTION
1.1. General
Sustainable design concept is the key requirement to present and future in
engineering design to ensure the safety. reliability and sustainability of the structure.
The design of floating platform using foam concrete on peat soil as a pedestrian
walkway is sustainable designs where the structure must he prevented from
settlement since the structure is build on the peat soil.
Peat soil is classified as soft soil with a high organic content. According to
Andncsse (1992), Peat in strict definition usually refers to the accumulation of a
purely one hundred percent organic material and the distinction between soil and
vegetative accumulation is not clear. JKR Malaysia (1995) defines peat soil as
extreme form ofsofi organic soil with organic content equal or more than 75°4.
Due to its softness and high corn when loading applied, constructing structure
above the peat soil will cause the structure to settle after a short period of time. To
remove the peat soil layer and replace it with other type of soil will he costly.
Therefore structure construct on peat soil must he light to a limit where the soil
hearing capacity of the peat soil still can support it. Here is where f6am concrete is
bringing in due to it characteristic of being light.
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Foam concrete is classified as one of the structural lightweight concrete.
(What is Foam Concrete. 2006) Densities of the foam concrete can be range from
350 kg/m' to 1600 kg/m' with the 28 days compressive strengths range from 0.2
N/mm2 to 12.0 N/mm2. Due to its low densities, foam concrete imposes little vertical
stress on the substructure -a particularly important attribute in areas sensitive to
settlement. Foam concrete is considered as environmental friendly material due to its
forming agent chemical properties of not producing harmful toxic substances to the
environment.
Pedestrian walkway is basically constructed beside the road, riverside or
between buildings for the pedestrian to walk from one location to another location.
Thus increase the connectivity of the pedestrian circulation. Since the pedestrian
walkways are only required to stand the loading of peoples walk over it, the plattbrm
basically is design take only minimum loading.
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1.2. Project Objectives
The main objective of this project is to investigate the optimum mix
proportion of the foamed concrete into high stability in water. This is preliminary
study before the design of floating foundation using foamed concrete as pedestrian
walkway. Before the design can be carried out, there are a few secondary objectives
need to be complete. First, required mix proportion of the foam concrete need to he
done in order to determine the required density and strength of the foam concrete to
be use. The properties of the peat soil need to be studied to understand the constraints
and difficulty of the peat soil will bring to the project. And the design standard and
requirement for the pedestrian walkway need to be stated.
1.3. Design Concept
The concept of this project is to design a foundation on top of the peat soil.
The idea is to replace some part of the peat soil with tamed concrete and put a
structure on top of it. The principle is that the combined famed concrete and
structure must he designed with a density lower or equal to the density of the
excavami soil.
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1.4. Scope of Study
To achieve the objectives of this project, the study will mainly tbcus on the
related elements of foam concrete, peat soil and floating platform pedestrian
walkway. The scope of studies will include:
a) Determine the properties and application of foam concrete.
b) Review the case study relevant to these project objectives.
c) Study the properties of the peat soil and difficulties will be face to construct a
substructure above it.
d) Study the feasibility of pozzolan fly ash (p. fa. ) as tine aggregates to
replacing sand in mix design.
e) Find the required density and compressive strength of the füam concrete to he
the replacement material.
f) Study and design the optimum mix proportion fur the experiment of this
project.
g) Producing concrete cube samples according to the designed mix proportions
at laboratory.
h) Experiment the cube samples under strength test, water permeability test.
floating test and durability test.
i) Designing the pedestrian walkway with according to the suitable mix
proportion tested.
j) Analyzing the suitable types of densities and mix proportion of loam concrete
to he use in the design of floating platform fi)r the pedestrian walkway.
k) Discussing on the experimental result and the analysis done and propose
recommendations fir the future study of this project.
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1.5. Project Outlines
This Final Year Project contains five chapters with Introduction, Literature
Review, Methodology. Analysis and Result, and finally Conclusion and
Recommendations. The summary of the report will be explained below:
" Chapter I Introduction
This chapter includes the introduction of foam concrete, peat soil and other
key elements that related to the project. the objectives and the scope of study
of the project.
" Chapter 2 Literature Review
This chapter containing the inf'ormation of this project which obtain from
reference books, journal, articles, report, case study and etc. The infimrmation
would include properties and characteristic of fbam concrete, fly ash and peat
soil, the constraints and difficulty which may face in the project, examples of
the research that relevant to this topic which had been done by other and case
study of'some application of the füam concrete.
" Chapter 3 Methodology
This chapter containing the description of'the materials and equipments used
to produce the tram concrete. The procedure of the mix design will he
evaluated in detail under this chapter. This also include the description of'the
tests will he cam out and the detailed procedures ot'the test.
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" Chapter 4 Result and Analysis
This chapter will contain all the results obtain on the experiment test and
analysis and design process of the project. Discussion on the result will also
include in this chapter.
" Chapter 5 Conclusion and Recommendations
This chapter will contain the conclusion of this project according to the result
obtain in chapter 4 and review the objectives achieved. Recommendations
will he stated for further study.
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CHAPTER 2
LITERATURE REVIEW
2.1. General
This Final Year Project (FYP) is entitled as Designing of'Floating Foundation
above Peat Soil Using Foamed Concrete for Pedestrian Walkway. The purpose of
this FYP is to design and produce a sample of floating foundation using suitable
density of foamed concrete and test it on the peat soil sample. In this chapter, the
properties, productions, applications and advantages of'the fbamed concrete and also
the forming agent will he review according to researches done by others. Purified Fly
Ash (p. f. a. ) is used in the production of tram concrete to replace sand as the fine
aggregate in this project. The properties and advantages of the p. f. a. will he further
reviewed in this chapter. Peat soil is another keyword for this project. Therefore,
properties and construction issue due to peat soil will he review in this chapter. Since
peat soil from difti: rent locations will have diflcrent classification, this project will
only looking on the peat soil in Sarawak. The cases studies of' the application of'
tanned concrete and floating foundation done by other researchers will include in
this chapter as a guideline and references fir this project.
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2.2. Foamed Concrete
Foamed concrete, also know as cellular concrete, aerated concrete or porous
concrete is a type of lightweight concrete that contain uniform distribution of air
bubbles throughout the mass of the concrete. According to Dhir. Ncwlands, &
McCarthy (2005), foamed concrete is a specialized product that contain more than 20%
by volume of air which achieved by incorporation of pre-formed foam or foaming
surfactant into a cemcntitious base mix. In its basic form foamed concrete is a blend
of sand, cement, and water (the base mix) and pre-formed foam, which is a mixture
of foaming agent (either synthetic or protein based), water and air. Foamed concrete
can have densities range from 400 to 160) kg/m` and with the compressive strength
range from 0.5 to 10 N-'mm' according to Aldridge (2(x)5). The application of foam
concrete is widely range from wall panels, floor, and foundation to void filling.
2.2.1. Development
Foamed concrete was first used in the Europe countries as early as I920's.
Since then the development of framed concrete had grown rapidly, especially in the
past few decades. Due to the improvement in material technology, production
equipments and research in producing quality framing agents in the last fifteenth
years, toamed concrete nowadays can he produced and placed on a large scale,
therehy widening the scope of this product construction applications in the industry.
According to Aldridge. 2tN15, r. l: a. or g. g. b. s (Ground Granulated Blast
Furnace Slag) can he use as fine aggregate for }iumuel concrete, along with other
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kind of fillers in addition to sand, such as chalk or crushed concrete depending to the
purpose or application of the foamed concrete.
With ordinary concrete, there is a compact aggregate/sand skeleton, and
cohesion is achieved inside the cement mix: compression loads are mainly
transferred via this well-stacked aggregatc/sand skeleton. Foam concrete is
composed without coarse aggregate, but with a substantial volume of the tram
bubbles. The bubbles are typically 0.3-0.4 mm in diameter, surrounded by cement,
the highest concentration being near the plateau border where there is the
conjunction of three foam bubbles. In foam concrete mortar, these bubbles provide
the stability of the fbam concrete. Once the material hydrates, load transfer takes
place via the cement matrix around the bubbles. (Cox & Dijk. 2002)
2.2.2. Characteristic
Foamed concrete is defined as tree-flowing, self-compacting and self-
levelling and theretiore expected to give a collapse slump in dump test (Dranstield.
2000). In general, the lower the density of the concrete, the lower the strength of the
tiºrmed concrete will be. Replacing air bubbles (tram) inside the concrete to replace
the coarse aggregate will further reduce the density and the strength of the concrete.
The physical properties of the tiamcd concrete are mainly depends on the quantity of
cements, fly ash, aggregates. tillers, and volume of entrained tram.
Table 2.1 compare some general characteristic of' the fclanllYl concrete with
vanes dn- density. Those characteristics shows that tamed concrete «tl«wer density
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will have lower compressive strength, thermal conductivity, modulus of' elasticity
and drying shrinkage.
Table 2.1: Typical properties of foamed concrete (Aldridge. 2005)
DRY COMPRESIVE THERMAL MODULUS OF DRYING DENSITY. STRENGTH. CONDUCTIVITY. ELASTICITY. SHRINGKAGE,
kg/m' Nimm' W/mk kN/mm2 400 0.5-1.0 0.1 0.8-1.0 0.3-0.35 600 1.0-1.5 0.11 1.0-1.5 0.22-0.25 800 1.5-2.0 0.17-0.23 2.0-2.5 0.20-0.22 1000 2.5-3.0 0.23-0.30 2.5-3.0 0.18-0.15 1200 4.5-5.5 0.38-0.40 3.5-4. O 0.11-0.09 1400 6.0-8.0 0.50-0.55 5.0-6.0 0.09-0.07 1600 7.5-10.0 0.62-0.66 10.0-12.0 0.07-0.06
There are several other general characteristic of the foamed concrete which as
equally important in making foam concrete differ from the nominal concrete.
a) Low coefficient of permeability
The hydraulic conductivity of porous materials will decreases with an
increase in amount of air in the pores of the material. Since foamed concrete is made
up with a matrix of non-interconnecting micro bubbles, or air voids, thus the material
has a relatively low pcnneahility. (foam Concrete l. td, 2008)
b) Low water absorption
The solid matrix of cementitious slurry surrounding the fine cell structure of
the foamed concrete greatly reduces the capillary action of moisture through the
material.
W/mk kN/mm` %
1U
c) Freeze/thaw resistance
Primarily due to extremely low water absorption of foamed concrete, the
capillary water absorption (actual saturation degree) into accessible pours of' the
material never reaches a point of critical saturation (critical saturation degree), at
which point damage could occur.
d) Thermal insulating properties
Thermal insulation properties, k is the ability of a material to resist the flow
of heat. Since the makeup of low density füamcd concrete contains very large
amount of air content in the closed cell structure (up to 80% air), which provides fi r
good insulating properties. The high air content also provides fior good sound
insulating and excellent fire resistance qualities of the material. According to Aldrige
in Characteristic of Foamed Concrete (2(x)5), a 1000 kg/m` density foamed concrete
would have ak value of 0.3 w mk which compares to aI .S w/ink typical sand
cement screed, making the tamed concrete six times more thermally efficient.
Obviously the concrete will have a much greater strength, but when used in the
correct circumstances this would not create a problem.
Table 2.3 compare the thermal conductivity of foamed concrete with other
material. From the table, it is shown that fiºamed concrete have much lower thermal
conductivity value that marble concrete and clay brick, which make it more
of ectivcly used as a thermal insulation material.
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Table 2.2: Comparison of thermal conductivity resistance between turned
concrctc and othcr matcrials (Stray-Bcton Inc.. 2008)
Materials Density (kg/ma) Thcrmul Conductivity
(w/mk) Marbic 2700
Concrete 2400
Porous clay brick 2000
Foamcd concrete Foamed concrete
12(X)
1000
Foamed concreic 800
Foamed concrete 600
Foamed concrete --- Cork
Silicate cotton
Foamed poIvst)Tene
Foamed poIyst}Tene
400
100
1(x)
25
2.9
1.3 0.8
0.38
U. 23
0.1 8
0.14
0.03 0.032
0.030
0.022
Figure 2. I: Thernial conductivity vcmius doisiticw of fbunutil concrete. (Stroy-
Eichen Inc., 2(X)$)
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