OriginalPartial Replacement of Course Aggregate With Waste g

8/13/2019 OriginalPartial Replacement of Course Aggregate With Waste g

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FINAL YEAR PROJECT PROPOSAL

PARTIAL REPLACEMENT OF COARSE

AGGREGATES WITH WASTE GLASS.

BY: CALVIN DETE.

REG. NO: F16- 0709 /07

PROJECT SUPERVISOR:

MR.MWERU

Submitted in partial fulfillment of the award of Bachelor of Science Degree in Civil Engineering

DECLARATION

I, Calvin Dete, do declare that this report is my original work and to the best of my knowledge, it has not

been submitted for any degree award in any University or Institution.

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Signed______________________________________________ Date ____________

Calvin Dete.

CERTIFICATION

I have read this report and approve it for eamination

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Signed_______________________________________________Date_____________

ACKNOWLEDGEMENTS

I am indebted to my lecturers, colleagues and friends who have assisted me in preparation of this pro!ect

by giving guidelines, advice and comments. "y sincere thanks go to my supervisor "r. #!uki for his

immense support, encouragement and positive criticism during the pro!ect and report writing without

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whom this work couldn$t have been reali%ed. &lso I would like to thank the Civil 'ngineering staff

members and my colleagues who guided and assisted me in accomplishing this research work.

In addition, I would greatly like to thank my family and friends who stood by my side throughout my

studies, and anyone else whose input facilitated my life throughout college.

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DEDICATION

(irst, I would like to dedicate this research pro!ect to &lmighty )od who has blessed me and brought me

to this point.

Secondly, I dedicate this research work to my mum and my dad, and all my family members. *heir

undying commitment to my education and unwavering support throughout this course has been a true

revelation. "ay the +ord bless abundantly bless you.

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TABLE OF CONTENTS

Page

Declaration ....ii

&cknowledgement .......iv

Dedication..v

*able of Contents.................................................................................................. vi

+ist of figures....

+ist of tables.i

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CHAPTER ONE

-. Introduction...........................................................................................................-

-.- /ackground....................................................................................................-

-.0 1roblem 2ustification..............................................................................................-

-.3 1roblem Statement..0

-.4 5esearch ob!ectives................................................................................................0

-.4.- 6verall 6b!ectives...............................................................................................0

-.4.0 Specific 6b!ectives....0

-.7 5esearch hypothesis..............................................................................................3

-.8 Scope of Study..3

CHAPTER TWO

0. 6verview......................................................................................................4

0.- +iterature 5eview.....................................................................................................4

0.0 1hysical 1roperties of )lass..............................................................................7

0.0.- &ppearance....7

0.0.0 Specific )ravity and 5elative Density.............................................................7

0.0.3 )radation...8

0.0.4 Durability and 9orkability...8

0.0.7 Shear Strength..:

0.0.8 Compaction..;

0.0.: 1ermeability..08

4.0. Slump *est.....0:

4.3. Compressive Strength *est...............................................................................0;>3

4.3.- "odes of (ailure3>34

4.4. *ensile *est.................37

4.7. (leural Strength *est ...............38>3:

4.7.- *esting /eams for (leture.3374

LIST OF FIGURES

(ig -? Sieve arrangement -4

(ig 0? :7@ Coarse aggregate replacement mode of failure..........3-

(ig 3? 47@ Coarse aggregate replacement mode of failure ..30

(ig 4? -7@ Coarse aggregate replacement mode of failure ......33

(ig 7? 3@ Coarse aggregate replacement mode of failure......34

(ig 8? 3@ replacement after fleture ..............................................3;

(ig :? 3@ replacement before fleture ..............................................................3;

(ig ;? Slump )raph...........................................................................................0:

(ig


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LIST OF TABLES

*able -? Coarse )lass &ggregate &nalysis ............-8? Compressive Strength 5esults..00

*able :? Summary of Splitting *ensile *est 5esult....................................................04

*able 8? Summary of average crushing results..................................................................-74

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PARTIAL REPLACEMENT OF COARSE AGGREGATE WITH WASTE GLASS IN

CONCRETE BLOCKS.

1.0 INTRODUCTION

1.1 BACKGROUND

)lass is a transparent material produced by melting a miture of materials such as silica, soda ash, and

CaC63 at high temperature followed by cooling during which solidification occurs without

crystalli%ation. )lass is widely used in our lives through manufactured products such as sheet glass,

bottles, glassware, and vacuum tubing. )lass is an ideal material for recycling. *he use of recycled glass

in new container helps save of energy. It helps in brick and ceramic manufacture, and it conserves raw

materials, reduces energy consumption, and the volume of waste sent to landfill.

9aste glass is a ma!or component of the solid waste stream in many countries. It can be found in many

forms, including container glass, flat glass such as windows, bulb glass and cathode ray tube glass. &t

present, although a small proportion of the post consumer glass has been recycled and reused, a

significant proportion of waste glass generated in Aenya is sent to landfill.

)lass is a -@ recyclable material with high performances and uniBue aesthetics properties which

makes it suitable for wide>spread uses. /esides, the current recycling states pose great pressures on glass

recycling and reusing. *he use of glass as aggregates in concrete has great potential for future high

Buality concrete development. *his research will focus on the applicability of waste glass to civil

engineering applications. )lass cullet utili%ed as an aggregate can incorporate mied glass that have been

crushed and screened to remove debris and oversi%ed particles. *his system provides a use for glass

materials not currently recycled.

1.2 PROBLEM JUSTIFICATION

Demands on building material have increased from time to time due to the increasing population and

urbani%ation. &mong the material demanded is coarse aggregate and in the phase of sustainability in

construction, utili%ation of waste material has been encouraged because recycling of this material will

help in protecting the environment from land fill disposal of the broken waste and also the granitic

Buarrying of the coarse aggregate will be significantly reduced.


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(rom engineering standpoint, broken glass or cullet appears to be an ecellent supplement for

replacement for natural aggregate in many construction applications. *he study will define the suitability

of waste glass as a construction aggregate in terms of its engineering performance and cost comparability

with natural aggregates.

1. PROBLEM STATEMENT

*he study will aim at evaluating the use of waste glass as a possible replacement of course aggregate in

concrete blocks so as to reduce the amount of waste glass to be land filled and as well as any resulting

risk to human health and also come up with light>weight, low cost concrete blocks of normal concrete .

9hat is needed is an aggregate comprising material of low commercial value, which can be

complemented with natural aggregate to provide concrete of eBuivalent, or improved physical properties.

9ith respect to the construction industry and engineering profession, these new materials may not only be

more economically advantageous than traditional granular materials but may also outperform them.

=ence waste glass aggregates could be considered as a viable alternative. *he factors to be considered

will be,

#atural aggregate locally available.

=ow cullet might supplement or complement the natural aggregate supply,

Supply and Buantity of cullet,

Si%e of cullet demand for given applications and

&pplicable local specifications and environmental regulations.

1.! RESEARCH OBJECTIVES

1.!.1 OVERALL OBJECTIVE

*o investigate the possibility of either partial or total replacement of conventional coarse aggregates with

waste glass in the manufacture of concrete blocks.

1.!.2 SPECIFIC OBJECTIVES

*o determine the material properties of waste glass.

*he study will


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*o investigate the availability and economic feasibility of the use for waste glass as

aggregates

1." RESEARCH H#POTHESIS

*his research aims at producing a concrete block which will be of low cost and having the same

engineering properties as conventional concrete. *he positive impact on the environment will also be felt

as a large Buantity of non>biodegradable waste glass will be recycled for use as opposed to being dumped

in landfills. *hus environmental conservation efforts will move in the right direction.

1.$ SCOPE OF STUD#

*he scope of this pro!ect will be to evaluate the use of waste glasses as a possible partial or totalreplacement of conventional concrete in the manufacture of concrete blocks.


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CHAPTER 2

2.0 OVERVIEW

2.1 LITERATURE REVIEW.

*he opportunity for using glass in construction application stems from the emergence of Buantities of

materials remaining from recovery and recycling activities, due to inconsistencies between the Buantities

of different colours of glass manufactured and the colour composition of glass waste streams.UA

produces over three million tonnes of waste glass annually, of which :-@ comes from waste containers.

*here is not much literature on the Aenyan solid waste management S9"E sector. 9hile poor

management of solid waste is a general problem in Aenya, it is probably worst in #airobi because of the

lack of consistent data in other parts of the country.

*he amount of waste glass has gradually increased over the recent years due to an ever>growing use of

glass products. "ost waste glasses have been dumped into landfill sites. *he land filling of waste glasses

is undesirable because they are not biodegradable, which makes them environmentally less friendly.

*here is huge potential for using waste glass in the concrete construction sector. 9hen waste glasses are

reused in making concrete products, the production cost of concrete will go down. 9hen used in

construction applications, waste glass must be crushed and screened to produce an appropriate design

gradation.

9aste glasses are used as aggregates for concrete. =owever, the applications are limited due to the

damaging epansion in the concrete caused by &S5 between high>alkali pore water in cement paste and

reactive silica in the waste glasses. *he chemical reaction between the alkali in 1ortland cement and the

silica in aggregates forms silica gel that not only causes crack upon epansion, but also weakens the

concrete and shortens its life. )round waste glass was used as aggregate for mortars and no reaction was

detected with fine particle si%e, thus indicating the feasibility of the waste glass reuse as fine aggregate in

mortars and concrete. In addition, waste glass seemed to positively contribute to the mortar micro>

structural properties resulting in an evident improvement of its mechanical performance. 5ecently, some

studies were carried out to suppress the &S5 epansion in concrete and find method to recycle waste

glasses. *he concrete containing 0@ waste glass reduced the epansion ratio by 4@. Shayan and Fu

reported fine glass powder for incorporation into concrete up to 3@ as a po%%olanic material suppressed


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the &S5. *opcu and Canba% reported the waste glass in si%e of 4>-8 mm used as aggregate in the concrete

reduced the compressive strength of concrete. *uncan showed the addition of waste glass powder -7@E

into concrete increased the compressive strength of concrete as much as -3@. AGsacGk also reported the

compressive strength of concrete with waste glass decreased -7 mm addition into concrete decreased the compressive strength of concrete as much

as 4@. 1ark, *opcu and Canba%, *uncan and AGsacGk reported in their studies the addition of waste glass

into concrete in crushed forms decreased the fleural strength. 1ark, *opcu and Canba% and AGsacGk also

reported in their studies the addition of waste glass into concrete in crushed forms decreased the splitting

tensile strength, while *uncan, reported an increase of 8@. Sangha, investigated the effect on concrete

strength of green glass as an aggregate replacement. *hey observed that increases in the compressive

strength values at the -@, 4@, and 8@ aggregate replacement by waste glass with >- mm particle

si%e were 3@, ;@ and 7@ as compared with control sample without waste glass but decrease in the

compressive strength value was 0@ at the 0@ replacement.

2.2 PH#SICAL PROPERTIES OF GLASS

*he technical feasibility of substituting glass waste or cullet blends for a given soilHaggregate component

should be based on demonstrating the eBuivalency of the cullet performance to that of the conventional

aggregate component. *he use of conventional aggregate materials in civil engineering construction

applications is based on an evaluation of classification and engineering properties. Classification

properties are those properties which help identify a material and engineering properties are those used

for engineering design.

2.2.1 A%%ea&a'(e

*he amount of debris in glass cullet can affect its engineering properties. Depending upon the glass

collection and sorting procedures, glass cullet may contain the following types of debris? paper, foil and

plastic labels, plastic and metal caps, cork, paper bags, wood debris, food residue, and grass.

Specifications should place a limit on the percentage of debris allowed in the cullet. )enerally, debris

levels should not eceed a maimum of - percent and in many applications 7 percent.

*he glass cullet particles are mostly angular with a small percentage flat or platy shape. *he angular

shape indicates a potential to cut or puncture a synthetic liner geomembraneE or similar material if placed

against this material. &pplications should avoid this direct contact.

2.2.2 S%e()*)( G&a+),- a' Re/a,)+e De'),-


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Specific gravity is a measure of a material$s density. *his determines the amount of voids in the

aggregate. Specific gravity values for crushed natural aggregate range from 0.8 to 0.;3. /ased on test

results done by =/5 'ngineering in the US, the specific gravities for coarse glass cullet ranged from -.si%e distributionE as the K...proportions by mass of a soil or

fragmented rock distributed in specified particle>si%e ranges.J )radation is a primary criterion for

roadway and engineering fill. It can affect engineering properties such as compaction, permeability,

filtration, and shear strength. *he gradation of glass cullet is generally similar to crushed rock and gravely

sand and is controlled by the cullet processing method. )radation is obtained by sieve analysis.

Specifications will dictate the gradation reBuired for each application.

)radation test results from Dames L "oore indicate that significant gradation change occurs when -

percent cullet is sub!ected to heavy impact compaction. *herefore, fill applications that use this type of

compaction such as fluctuating or heavy stationary loads should not use - percent cullet.

2.2.! D&a3)/),- a' W&4a3)/),-

Durability of a material is based on hardness and toughness. Durability was evaluated by Dames L "oore

from the +os &ngeles +.&.E abrasion tests using standard method &S*" C -3 -. Durability is a material

classification property that affects its suitability for roadway base course and fills under fluctuating loads.

)lass cullet$s resistance to abrasion is lower than that of natural aggregate. *he +.&. abrasion test

indicated that the percentage wear of glass cullet was 3 percent for -H4>inch minus si%e and 40 percent of

3H4>inch minus si%e. *his is almost two times greater than that of natural aggregate. *he #ebraska

Department of 5oads #D65E specifies limiting values for mineral aggregate used in roadway base

courses and foundation courses at 4 percent, and crushed rock used in base courses at 47 percent.


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9orkability is the ease with which an aggregate is handled and compacted. )lass cullet is generally

angular in shape, compared to crush rock subangularE and gravely sand subroundE the M inch minus

cullet has some potential to cut, puncture, or wedge into moving parts of construction eBuipment.

=owever, favourable compaction characteristics provide good workability of glass cullet and cullet>

aggregate miture.

2.2." S5ea& S,&e'g,5

&S*" D 873 -E defines shear strength as,.the maimum resistance of a soil or rock to shearing stresses.J

Shear strength is a design consideration that affects bearing capacity. *his shear strength is epressed by

the angle of internal friction, measured in degrees. *ypical granular soil have angle of friction ranging

from 0: degrees for loose, silty sandE to 77 degrees for dense, medium si%e gravelE. +imited direct shear

test data on glass cullet indicate a friction angle at 77 degrees. *his is slightly higher than the typical

natural aggregate. Dames and "oore suggested that this implied strength of glass cullet may not be

reliable and recommended five type$s tests to further define cullet shear strength. & summary of

subseBuent test results is presented in the table.


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*he 5>value relates indirectly to the strength of the material. *he value is commonly used to specify base

or sub>base aggregate. *he resilient modulus is a measure of a material$s stiffness used in pavement

design. *he resilient modulus of natural aggregate is typically about 3 ksi at a bulk stress of 07 psi.

"odulus for cullet does not appreciable change with repeated loading e.g., repeated traffic loadsE.Shear strength is a ma!or design consideration for construction with glass cullet in embankments,

roadway base courses, and engineering fill under foundations. *est results indicate that the strength of

cullet is about the same as natural aggregate. =owever, for specific applications such as fills under

fluctuating loads and roadways, only cullet mies up to 3 percent are recommended by Dames L "oore.

2.2.$ C6%a(,)'

&S*" D 873 -E defines compaction as the K...densification of a soil by means of mechanical

manipulation.J Compaction is a design consideration that effects density control. Compaction

characteristics include relationship of density and moisture content, effect of compaction method on

density and potential gradation change, and sensitivity of material to weather conditions.

Cullet and cullet>aggregate mitures have favorable compaction characteristics. )lass cullet aggregate

mitures generally do not eperience appreciable gradation changes with compaction. *he maimum

density values obtained from the "odified 1roctor compaction and vibratory compaction tests are about

eBuivalent for cullet>added fill materials. Density slightly increases with decreasing cullet content.

=owever, heavy field compaction eBuipment can significantly effect density values for - percent cullet

fills because of the gradation changes, *he compacted density of cullet is not sensitive to the moisture


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content, which means that cullet material can be placed and compacted during wet weather. &s a result,

construction downtime may be kept to a minimum.

2.2.7 Pe&6ea3)/),-

&S*" D 873 -E defines permeability as, K...the capacity of a rock to conduct liBuid or gas.J 1ermeability

is a design consideration in civil drainage applications such as foundations drainage, drainage blankets,

and french drains, and in leachate collection and gas venting layers. (or drainage fill material, high

permeability is usually more beneficial than low. *ypical granular soils washed gravel, sand or sand>

gravel mituresE have permeabilities ranging from .- to .- cmHsec. *he permeability of a granular

material depends on its gradation and density. Data reported on permeability tests of - percent glass

cullet have permeabilities ranging from .4 to .8 cmHsec for fine cullet and .-; to .08 cmHsec for

coarse cullet. *he cullet>aggregate mitures have permeabilities between - percent cullet and granular

soils. In general, permeability will increase with increasing cullet content, cullet si%e, and debris level but

will decrease with increasing compaction. *his is comparable to natural sand and gravel. *herefore,

drainage applications can use - percent glass cullet for fill material. Cullet also appears to have

favorable characteristics for use as filtration media in such applications as septic fields, leachate treatment

and water purification. =owever, further study of the filtration capacity is warranted.

2.2.8 T5e&6a/ C'(,)+),-

*hermal conductivity represents the ability of the material to conduct or resist heat flow. *hermal

conductivity is a design consideration that effects bedding and backfill for conduits or other heat sources.

*est data results indicate that glass cullet and cullet>aggregate mitures have slightly lower thermal

conductivities than natural aggregate. In other words, cullet conducts heat more slowly. *his slight

difference still allows cullet materials to be feasible for utility trench backfill.

2.2.9 F)/,&a,)'

&S*" D 873 -E defines a filter as, ... a layer or combination of layers of pervious materials designed

and installed in such a manner as to provide drainage, yet prevent the movement of soil particles due to

flowing water.J (iltration is a design consideration that effects clogging and plugging between ad!acent

layers. *he &merican 9ater 9orks &ssociation Standard / - was applied to cullet properties

gradation, specific gravity, shape, and hardnessE to determine suitability as a filtering media. *ypical

filtering media such as silica sand have reBuired effective si%es ranging from .37 mm to .87 mm. *he

gradation of fine glass cullet @>inch minusE tested by Dames L "oore ranged from .7 mm to 8.7 mm.

9ith additional sieving, the fine cullet appears to be feasible as an intermediate filtering media. Coarse


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cullet provides high permeability, but is not effective as a graded filter. Dames L "oore recommended

further direct measurement and study of cullet filtration capacity.

(iltration is a ma!or design consideration for all drainage type applications in direct contact with ad!acent

soil layers. (ilter fabrics may be used to provide the filtration function and prevent plugging and clogging

of the cullet layer. *hick non>woven geotetiles also offer puncture resistance.

2.2.10 Lea(5a3)/),-

)lass is a relatively inert material however, common contaminants from collection methods can

influence the chemical characteristics of glass feedstock. 6nly limited chemical test data is available for

recycled glass feedstocks. *oicity Characteristic +eaching 1rocedure *C+1E testing for metals, based

on analytical data provided by the Clean 9ashington Center indicates, K...all metals, ecept lead,

occurred at concentrations below the regulatory limit.J *he lead levels in some samples may be

associated with the lead foil wrappers on wine bottles in various cullet feedstocks. *C+1 organic

compounds were not detected, suggesting that organic compounds in cullet have a low leachability

potential. *he semi>volatile organic analysis indicated the presence of phthalate compounds, a

biodegradation product of plastics. *he variability in presence and concentration of lead and phthalates in

cullet samples can be attributed to whether cullet is screened for debris, the color of the cullet, and the

sorting and collection procedure for each cullet source.

+aboratory test results have been conducted for total lead and leachable lead by /(I using '1& "ethod

3-H8- and '1& "ethod -3 --H8- ;E. *he test results for all samples showed that total lead

concentrations were undetectable or at low concentrations similar to levels in natural aggregate. "ost

cullet source samples showed *C+1 lead results below the federal regulatory limit of 7 mgHl or

undetected.

&dditional laboratory leaching tests were conducted by Dames L "oore in accordance with &S*" D

4:day period.

In general, metal concentrations in glass cullet were at or below the metal concentrations

typically found in background levels of natural aggregate Contaminant levels of the cullet samples

decreased in concentration over time and are not at concentration of concern.

+eachability is a design consideration for glass cullet applications in contact with ground water or sub!ect

to infiltration into ground water.


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2. Sa*e,- a' Ha'/)'g

Safety concerns in handling glass cullet during production and construction include? eposure to

respirable particles and potential for skin irritations, cuts, or lacerations. )lass is primarily composed of

amorphous silica. &morphous silica is not considered to be a significant health ha%ard. Crystalline silica,

a health ha%ard known to cause fibrogenic lung disease, is not likely to be found, ecept in very low

amounts, in the post>consumer glass stream used for cullet. *est results conducted>by Dames L "oore

indicated that cullet samples contained less than one percent crystalline silica which puts glass cullet dust

in the nuisance dust category under 6S=&.

Skin irritations and cuts can be avoided through the use of protective clothing similar to that worn when

working with natural aggregates. *his includes heavy gloves, long>sleeve shirts, pants, heavy boots, hard

hats, hearing protection and eye protection.


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CHAPTER

.0.0 RESEARCH METHODOLOG#

.1.0 INTRODUCTION

*he pro!ect will involve analy%ing the effects of partially replacing ballast with glass wasteHcullets in a

concrete mi. *his will involve laboratory tests and each test will be conducted several times and the

averaged results considered. In this study, concrete mi design will employed and deductions derived

purely from the obtained results. *he following test will be done.

.1.1 SAMPLE COLLECTION AND PREPARATION

Sample of the waste glass will be collected from the Coca Cola and /eer dealers depot in #airobi and at

the selected pubs around 2u!a area. *he glass will be inspected to ensure that the debris and other forms of

impurities are removed and then crushed manually to the reBuired si%e.

.1.2 SAMPLING OF AGGREGATES

Samples should show the true nature and conditions of the materials which they represent. *hey should be

drawn from points known to be representative of the probable variations in the material. &t the laboratory

the main sample should be reduced to the Buantity reBuired for testing. *here are two ways of reducing

the si%e of a sample each essentially dividing it into two similar parts. *hese are

a: R)**/)'g

*he sample is split into two halves using a riffler 5iffle boE. *his is a bo with a number of parallel

vertical divisions, alternate ones discharging to the left and to the right. *he sample is discharged into the

riffle bo over its full width and the two halves are collected into the boes at the bottom of the chutes on

each side. 6ne half is discarded and riffling of the other half is repeated until the sample is reduced to the

desired si%e.

3: ;a&,e&)'g

*he main sample is thoroughly mied and in case of fine aggregates, it is damped in order to avoid

segregationE. *he aggregate is heaped into a cone and then turned over to form a new cone. *his is

repeated twice, the material always being deposited at the ape of the cone so that the fall of particles is

evenly distributed round the circumference. *he final cone is flattened and divided into Buarters. 6ne pair


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of the diagonally opposite Buarters is discarded and the remainder forms the sample for testing. If it is still

too large, it can be reduced further by Buartering. Care must be taken to include all fine material in the

appropriate Buarter.

.2. PARTICLE SI


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(ig -? Sieves

. DESIGN OF CONCRETE MIXES

*his is the process of selecting the correct proportions of cement, fine and coarse aggregate, water and

sometimes admitures to produce concrete having the properties specified and desired i.e. workability,

compressive strength, density and durability reBuirements by means of specifying the minimum or

maimum waterHcement ratio.

..1 PRINCIPLES OF DESIGN

S,&e'g,5 Ma&g)'

Due to variability of concrete strengths, the mi must be designed to have higher mean strengths than the

characteristic strength. *he difference between the two is the "argin. *he margin is based on the

variability of concrete strengths from previous production data epressed as a standard deviation.

W&4a3)/),-

*wo alternative methods were used to determine workability Slump test which is more appropriate for

higher workability mies and the compacting factor test which is particularly appropriate for mies which

are applicable to mies compacted by vibration.


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F&ee > ?a,e&

*he total water in a concrete mi consists of water absorbed by the aggregate to bring it to saturated

surface N dry condition and the free N water available for hydration of cement and for the workability of

the fresh concrete. *he workability of fresh concrete depends on a large etent on its free N water content.

In practice, aggregates are often wet and they contain both absorbed water and free surface water so that

the water added to the mier is less than the free N water content. *he strength of concrete is better related

to the free N waterHcement ratio since on this basis the strength of concrete does not depend on the

absorption characteristics of the aggregates.

T-%e * agg&ega,e

*wo characteristics of aggregates particles that affect the properties of concrete are particle shape and

surface teture. 1article shape affects workability of the concrete and the surface teture affects the bond

between the cement matri and the aggregates particles and thus the strength of concrete. *wo types of

aggregates are considered for design on this basis Crushed and Uncrushed.

Agg&ega,e g&a)'g

*he design of mies will be based on specific grading curves of aggregates. *he curves of fine aggregates

must comply with grading %ones of /S ;;0.

M)@ %a&a6e,e&

*he approach to be adopted for specifying mi parameters will be reference to the weights of materials in

a unit volume of fully compacted concrete. *his approach will reBuire the knowledge of epected density

of fresh concrete which depends primarily on the relative density of the aggregate and the water content

of the mi. *his method will result in the mi being specified in terms of the weights in kilograms of

different materials reBuired to produce -m3 of finished concrete.

..2 STAGES IN MIX DESIGN

S*&)' -? Selection of *arget 9aterHCement 9HCE ratio

S*&)' 0? Selection of free N water content.

S*&)' 3? Determination of cement content

S*&)' 4? Determination of total aggregate content

S*&)' 7? Selection of fine and coarse aggregate content

S*&)' 8? "i proportioning

.! BATCHING OF CONCRETE MATERIALS

(ollowing the mi design process, concrete materials Cement, (ine and Coarse &ggregatesE should be

prepared early enough before the concrete works begins. *his allows the smooth running of the pro!ect.

/atching of materials will be done by weight. *he advantage of weight method is that bulking of


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aggregates especially fine aggregatesE does not affect the proportioning of materials by weight unlike

batching by volume method. /ulking of sand results in a smaller weight of sand occupying a fied

volume of the measuring container thus the resulting mi becomes deficient in sand and appears stony

and the concrete may be prone to segregation and honeycombing. Concrete yield may be reduced.

*he batch weights of aggregates determined in the mi design process are based on a saturated surface N

dry conditions. 9hen working with dry aggregates, the following options may be adopted to achieve

saturated surface N dry conditions

-. *he batch weights of fine and coarse dry aggregates reBuired for the trial mi are calculated by

multiplying the batch weights derived from mi design by - -O ,where & is the percentage by

weight of the water needed to bring the aggregate to the saturated surface N dry condition.

0. *he dry aggregates are brought to a saturated surface N dry condition before miing process by addition

of the reBuired amount of water for absorption by the aggregate according to /S -;;- N -07?-


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*he free N water reBuired to produce concrete of a specified slump depends upon the characteristics of the

aggregate. *he grading of coarse aggregates, provided it complies with the reBuirements of /S ;;0, has

little effect on water reBuirement of a concrete mi. *he grading of fine aggregate has a considerable

effect on the water reBuirement of the concrete. Changing the grading of sand from a coarse one e.g.

0@ by weight passing the 8 m test sieveE to a finer one e.g.


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3E *he cone will then be filled with fresh concrete in three layer with each layer compacted with 07

strokes of the tamping rod.

4E &fter filling the mould, the top surface will be struck off by means of rolling action of the tamping rod.

7E Immediately after filling, the cone will be slowly and carefully lifted.

8E Immediately after removal of the mould the slump of the unsupported concrete will measured and

recorded.

.$ TESTING THE PROPERTIES OF HARDENED CONCRETE

.$.1 DETERMINATION OF COMPRESSIVE STRENGTH > CUBE TEST TO BS EN 1290 >

22000

.$.1.1 Ca,)'g * (3e

*he specimens were cast in iron moulds generally -7mm cubes. *his conforms to the specifications of

/S -;;- N 3?-


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with the platens of the testing machine that is the position of the cube when tested should be at right

angles to that as cast. *he load will then be applied at a constant rate of stress of approimately eBual to

-7 #Hmm0 to failure. *he readings on the dial gauge will be recorded for each cube

*he crushing strength is influenced by a number of factors in addition to the waterHcement ratio and

degree of compaction. *hese are

The type of cement and its quality. /oth the rate of strength gain and the ultimate

strength may be affected.

Type and surface of aggregate. &ffects the bond strength.

Efficiency of curing. +oss in strength of up to 4@ may result from premature drying

out.

Temperature. In general, the initial rate of hardening of concrete is increased by an

increase in temperature but may lead to lower ultimate strength. &t lower temperatures,

the crushing strength

.7.0 FLEXURAL TEST MODULUS OF RUPTURE:

.7.1 OBJECTIVE

*o measure the strength of concrete by sub!ecting concrete beams to fleure. *he fleural test measures

the force reBuired to bend a beam under three point loading conditions. *he data is often used to select

materials for parts that will support loads without fleing. (leural modulus is used as an indication of amaterials$ stiffness when fleed. Since the physical properties of many materials especially

thermoplasticsE can vary depending on ambient temperature, it is sometimes appropriate to test materials

at temperatures that simulate the intended end use environment

APPARATUS

Concrete beam specimens

Standard rig for modulus of rupture

PROCEDURE

*he beam specimens were removed from their curing positions and placed on the testing machine whilst

still in the wet condition. *he surfaces were cleared of any loose material and the beam ais aligned with

the ais of the machine. *he load was applied at a rate of -:; #Hmin until the specimen failed.


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.8.0 INDIRECT SPLITTING TENSILE: TEST

.8.1 OBJECTIVE

*o determine the tensile strength of concrete specimen.

APPARATUS

Compression *esting "achine

Concrete cylinder specimens

PROCEDURE

& concrete cylinder was placed with its ais hori%ontal between the platens of a testing machine, and the

load was increased until failure by splitting along the vertical diameter took place.


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CHAPTER !

!.0.0 RESULTS ANAL#SIS AND DISCUSSION

!.1.0 PARTICLE SI


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Ta3/e 2

!.1.1.1 Ca&e Agg&ega,e S)e+e A'a/-).

Sieve si%es

mmE

9t. retained

gE

9t. passing

gE

@ retained Cumulative @

retained

Cumulative @

passing

4 07 . . -.

3 07 . . -.

07 :: 0403 3.; 3.;


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*able 3

!.1.1.2 F)'e Agg&ega,e S)e+e A'a/-).

Sieve si%es

mmE

9t. retained

gE

9t. passing

gE

@ retained Cumulative @

retained

Cumulative @

passing

0.3: 4:.7 0470.7 -.


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!.2.0 SLUMP TEST


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&s shown in *able below the slumps are in the /S recommended range of 3>8, indicating that the test

results are valid in this eperiment. It can be seen that the workability of glass containing 47@ glass had a

higher slump than the rest, this is Buite not reasonable since workability is governed by the surface area

and shape of the aggregate.

*able 4? Summary of the slump test results

Coarse aggregate replacement @E Slump mmE

@ 3:

-7@ 3-

3@ 37

47@ 74

8@ 3--8?---;?-


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APPENDIX A

CONCRETE MIX DESIGN TABLE

S!"#$ I!$% R$&$'$()$/C"*)+*"!i

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C5 .1969.....-336......103.#/%

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