Mai Skool Project

MEASUREMENT AND CONTROL OF MOISTURE CONTENT OF AGGREGATES, WOOD AND BRICK USED ON CONSTRUCTION SITE

BY

BORISANMI HENRY MONDAY F/HD/07/3510077

DEPARTMENT OF BUILDING TECHNOLOGY SCHOOL OF ENVIRONMENTAL STUDIES YABA COLLEGE TECHNOLOGY YABA LAGOS

NOVEMBER 2009

1

MEASUREMENT AND CONTROL OF MOISTURE CONTENT OF AGGREGATES, WOOD AND BRICK USED ON CONSTRUCTION SITE

BY

BORISANMI HENRY MONDAY F/HD/07/3510077

PROJECT WORK SUBMITTED TO THE DEPARTMENT OF BUILDING TECHNOLOGY IN SCHOOL OF ENVIRONMENTAL STUDIES YABA COLLEGE TECHNOLOGY.

IN PARTIAL FULFILMENT OF THE AWARD OF NATIONAL DIPLOMA IN BUILDING TECHNOLOGY

NOVEMBER 2009 2

CERTIFICATION This is to certify that the project: measurement and control of moisture content of aggregate, wood and timber used on construction site. Submitted to the Department of Building Technology for the Award of Higher National Diploma (HND) Building Technology is a record of work carried out by: BORISANMI HENRY MONDAY {F/HD/07/3510077} Of The Department of Building Technology Yaba College of Technology

BORISANMI H. M. Author’s name

BLDR. C. T UDOH Supervisor’s name

BLDR. ATERE O. V. Head of Department

………………… Signature

………………... Signature

………………… signature 3

………………….. Date

…………………. Date

……………………. Date

DEDICATION This project is dedicated to Almighty God the creator of heaven and earth for His infinite mercy and protection throughout my study period. And also to my beloved parent and family of: Ven. & Mrs. S.A Borisanmi for their support, both financial and morally throughout the course of my study.

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ACKNOLEDGEMENT

I want to use this medium to acknowledge my able supervisor “Bldr C.T. Udoh for his support and supervision towards the success of this project work. Also appreciate the effect of Mr. Odunekan for his great effort during my practical work, thanks a million. My gratitude goes to my parent Ven & Mrs S.A. Borisanmi, my brothers and sisters, “the husband, the wife” “Ven & Mrs. Agboola, Mr & Mrs Famodimu, Mr & Mrs. Gbemiga Borisanmi Jnr., Sis. Yemi and Sis. Toyin. You are the best family in the world thanks. My regards also goes to my cousins Mr. Irewole Oni and Walex, we are just like blood brothers, thanks for the support during my stay both at home and school. May God bless you real good. I say a powerful thank you to my Mentor Tosin Martins and wife for the advice and support financially.

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At this junction I acknowledge my indebtedness to all to my friends Richard, Alli-Balogun, Kayode, Bimpe, Lanre Awoyemi, Dotun, Tope, Opeoluwa, Yinka, Aleshinloye Abiodun, Dennis, Samuel, williems, Ydallar, Instinct productions in general + others and to my entire course mate, you are all wonderful. Lastly I can not but thank the authority ‘Yaba College of Technology’ for giving the opportunity to be one of their students. Thanks. Great Yaba Tech.

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PREFACE This project, “Measurement and Control of Moisture Content of Aggregate, Wood and Bricks used on construction site” is one of the criteria for the award of Higher National Diploma (HND) in the school of Environmental studies, Yaba College of Technology. Through this project the author is now familiar how to determine moisture content of construction materials.

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TABLE OF CONTENTS Certification

i

Dedication

ii

Acknowledgement

iii

Table of Contents

iv

Abstract

v

CHAPTER ONE:

INTRODUCTION

1.0

Background of the Study

1

1.1

State of the Problem

3

1.2

Aims and Objectives

4

1.3

Significance of The Study

5

1.4

Research Question

5

1.5

Scopes and Limitation

6

CHAPTER TWO:

LITERATURE REVIEW

2.1

Aggregates

7

2.1.

Types of Aggregates

7

2.2

Production of Aggregates

8

2.3

Production of Fine and Coarse Aggregates

8

8

2.4

Shape and Surface Texture of Aggregate

10

2.5

Table 1: Classification of Aggregate Shape

10

2.6

Storage of Aggregate

11

2.7

Grading Of Aggregate

11

2.8

Sieve or Screen Analysis of Fine And Coarse Aggregate

12

2.9

Sampling of Aggregates

12

3.0

Properties of Aggregate

13

3.1

Bond of Aggregate

13

3.2

Strength of Aggregate

14

3.3

Other Mechanical Properties of Aggregate

14

3.4

Required Characteristics of Good Aggregate

15

3.5

Used Of Aggregats

16

3.6

Importance Of Aggregates

16

3.7

Special Aggregates

17

3.8

Moisture Content

17

3.9

Effects of Moisture Content

19

4.0

How Moisture Penetrate Into the Aggregate

20

4.1

Sand

22

4.2

Bulking Of Sand

24 9

4.2

Bulking Of Coarse Aggregate

26

4.3

Fig IV: Range Of Moisture as They Affect Aggregate State.

26

4.5

Absorption and Surface Moisture

26

4.6

Measurement of Moisture Content

4.7

Control of Aggregate from Mositure On Site 29

4.8

Wood

30

4.9

Wood Properties

31

5.0

Hardwoods

32

5.2

Types of wood

35

5.3

Moisture in wood

36

5.4

Influence of moisture content

38

5.5

Brick /Block

39

5.6

Manufacture of Bricks

40

5.7

Brick Laying

41

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CHAPTER THREE:

RESEARCH METHODOLOGY

3.2

Population for The Sample

44

3.3

Samples

44

3.4

Sample Selected

45

3.5

Moisture Content Test

45

3.6

Used Apparatus

46

3.7

Drying Method

46

3.8

Method Data Analysis

47

CHAPTER FOUR:

ANALYSIS OF DATA AND DISCUSSION OF RESULTS

4.1

Moisture Content Test

48

4.3.

Findings/Results

50

4.4

Discussion Of Results

50

11

CHAPTER FIVE:

CONCLUSION AND RECOMMENDATION

5.1

Conclusion

51

5.2.

Recommendation

51

5.3

Suggestion For Further Studies

53

5.4

References

54

5.5

Appendix

56

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ABSTRACT This project is based on the measurement and control of moisture content of Aggregate, Wood and Bricks used on construction site. Dry method was used in this project work. Under the drying method, oven drying was used to determine the moisture content of the aggregate. The aggregates used for the test include fine aggregate (natural pit sand) and coarse aggregate (natural pit gravel and crushed gravel). Wood: Mariana (softwood), itara (hardwood), Arere (softwood), Parana(softwood), Eku (hardwood), Balsa(Hardwood), mahogany(hardwood). And also Brick/block. Finally, it was found that the method used was relevant and effective for determination of moisture content of construction materials.

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CHAPTER ONE 1.0

INTRODUCTION

1.1

BACKGROUND OF THE STUDY

Building /shelter is one of the major needs of human beings, it is mostly constructed by engineers, builders or contractors to meet a number of different functional requirements. While it is exposed continuously to a wide varieties of destructive agencies of forces.

The most vital aspect of the processing of construction is the decision bothering on the choice of measurement and control of moisture content of aggregate used on construction site that will be able to satisfy the basic principle’s of modern construction works in order to achieve its purpose and requirements.

Blackledge (1990) stated that: Aggregate are inert materials (i.e. chemically uncreative component concrete however gives economical, durable materials. Aggregate are classed as fine and coarse aggregates. Generally, various sands are used as fine aggregates and coarse aggregate are either water run gravel or crushed rocks quality of product.

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Therefore, engineer must however be satisfied that the source selected will consistently supply the quality of aggregates which he has approved. To my site, a network of good construction is a necessity and not a luxury. These aggregates are needed to improve good construction on our site, before we can achieve this proper measurement and control of moisture present in the aggregates must be taken into consideration. That is, the mass of water in a simple of material such as sand and gravel contain should be known before adding more at the mixer so that the total amount of water in a mix can be controlled and consistency ensured.

Also, the engineer or builder in construction site is responsible for the carrying out of this operation before the actual progress of work for efficiently and effectiveness in order to boost good workmanship and sensivity of the concrete/structural member of the work.

Orehard (1990) reported that the measurement of the moisture content of aggregate is basically a very simple operation but it is complicated by several factors. Aggregate will absorbed a quantity of water depending on its type and thus, the water content can be quoted in terms of the weight of aggregate, when absolute dry surface and when wet the water content can be 15

free water content or the total water content which include the absorbed water plus the free water. For site used, the method adopted must be accurate and must need only simple apparatus that can easily be replaced if damaged. Method of making the determination attainable include; i.

Drying method

ii.

Displacement method gauging the size of sample by weight

iii

Displacement method gauging the size of sample by volume. By using any of the above methods, it will help the builder to achieve quality aggregate free from moisture for construction works.

1.1

State of the Problem

The problem caused by moisture on aggregate attribute in construction work includes; I.

Strength is normally considered to be the most important property in relation to mature concrete. It is noted that during concreting, to check moisture content of aggregate prior to batch so that accurate adjustment of batch weights can be made necessary: batch quantities of aggregate must be increased if free water, present and the amount of free water in the aggregate should be deducted from 16

the water to be added. Excess water definitely wills reduces/affect the strength produced by the aggregate. II.

Workability is defined as the property of concrete, which determine of aggregate to be place compacted and finished. Major factor affecting workability is water content (usually expressed as volume in liters per cubic meter of concrete). For a given aggregate size and type workability is highly sensitive to changes of water content-for example, in the case of 20mm. irregular aggregate, a water content of 160litres per cubic metre would result in high workability, also affecting workability are maximum aggregate size and shape. Its depend on the mix ratio which end up resulting to affect the workability.

1.5

Aims and Objectives

The aim of this research is to measure moisture content of aggregates used on the construction site. The objectives are; i.

To determine moisture content by using Drying method

ii.

To know the moisture content by using displacement methods ganging the size of sample by weight.

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1.6

Significance of The Study

This research is to reveal to the various builder/student the required water content of every mix in construction aggregate, whenever the aggregate is moisturized, so as to achieve standard mix ratio. Presence of large content of moisture in wood (timber) would inhabit growth of algae, which causes decay of timber. In molded block/bricks would cause the unhydrated cement to hydrate to a large extent. Therefore the control of moisture content of timber to the minimum amount would enable such timber to provide the service intended to serve over the considerable long time without being affected by algae. Enhancing the moisture content of the moulded bricks/blocks on the other hand would help material’s producers/manufacturers to produce sound blocks/bricks. 1.7

Research Question -

What are the effects of the increase in water content on freshly mixed concrete using aggregates of varying conditions?

-

Are there any differences in the weight of aggregates when their conditions are altered?

-

Are there any allowances for moisture in the calculation of batch quantities?

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-

As a result of present of moisture on wood, what is the likely defect caused by moisture?

-

Are there any form of deformation on brick/blocks as a result of moisture/

-

Are there any differences between natural and artificial aggregate, in what area their function differ from the other.

-

What is the best method of drying wood to a required level of moisture content?

-

Can aggregate make a considerable difference to the properties of wet concrete.

1.5

Scopes and Limitation This study is focused on the measurement and control of moisture content of aggregate (used on concrete making), wood, blocks/bricks used on construction sites. Study will be based on fine and coarse aggregate.

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CHAPTER TWO 2.0

LITERATURE REVIEW

2.1

AGGREGATES

Smith (1978) stated that, An aggregate is a material in granular or particle form, such as sand or gravel, which is added to the class of materials known as binders (e.g cements, hydraulic limes, plaster and bitumen) to produce a solid mass on hardening, since most aggregates are inert and undergo no chemical action with the binder, the strength of the combine mass depend on; a.

The specific adhesion or sand which develops between aggregate and binder.

b.

The mechanical key or interlock which develops between the constituent particles in virtue of their shape, size and surface texture.

2.1.

TYPES OF AGGREGATES

Smith (1978) says that: there are two type of aggregate natural and artificial. Natural aggregates mostly used has a relative density of about 2.6 although both higher density and lower density material is used for special purposes; nearly all the artificial aggregates have a low relative density.

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NATURAL AGGREGATES The natural aggregates available vary in different part of the country as consequently do their properties. The main rock groups suitable for concrete are basalt, flint gabbros, granite, gristone, limestone, porphyry and quartzite. ARTIFICIAL AGGREGATES Artificial aggregate include crushed brick, blast furnace slag and numerous light weight and special aggregates.

2.2

PRODUCTION OF AGGREGATES

2.3

PRODUCTION OF FINE AND COARSE AGGREGATES

Sand and gravel are obtained either from pits or by dredging from the bottom of rivers or from the sea bed. Pits are termed “wet” or “dry” according to the water level in the vieinity, although some pits which would otherwise be wet are dried out by pumping. The deposit are usually covered with overburden which has to be removed by scrapers, mechanical shovel, dragline or by always straight forward owing to the presence of faults and dips in the gravel seams, and unless care is taken to remove these materials occasional load of dirty aggregates occur.

21

The sand and gravel are then excavated by mechanical shovels in dry pits: by dragline in both wet and dry pits, and by means of crane and grab, or suction pumps, in wet pits. Gravel seams often orclic beds of clay, and it is especially necessary that the inclusion of lumps of clay in the gravel should be avoided since even with vigorous washing the clay lumps are extremely difficult to remove. The danger of the inclusion of clay lumps is greater in wet pit than in dry pit where dragline or grabs are used, because the driver is unable to see the bottom, and therefore, to control the depth to which be digs.

The mixed gravel and sand is usually conveyed from pit to the screening plant by conveyor belt or in light trucks or by pipeline when the gravel is raised by a suction pump, conveyor belt are commonly used to raise the materials from ground level and sans is carried out either by means of cylindrical rotating screen or by the more modern vibrating screens. A recent improvement to vibrating screens has been made by carefully designing then to produce a resonant effect. The sand and dirty water are usually carried away together and are then dewatered by another mint. From the screening unit, the sand and gravel are fed by gravity into suitable hoppers. Oversize materials goes to a crusher and is often retain for rescreening. 22

The sand at some pits is treated further to modify its grading, by means of classifier (Brooks, 1979) 2.4

SHAPE AND SURFACE TEXTURE OF AGGREGATE

Smith (1978) recorded that, aggregate shape can make a considerable difference to the properties of the wet concrete. The shape may be classified as rounded, irregular and angular. Surface texture can be divided into six categories: glossy smooth, granular, rough, crystalline and honey combed. It appears that the rougher the surface texture the greater the bind the strength possible between the particles and cement matrix. In a similar manner a larger adhesive strength should be possible with the bigger area of angular aggregate than rounded material.

2.5

TABLE 1: CLASSIFICATION OF AGGREGATE SHAPE SHAPE Rounded Irregular Angular

2.6

SOURCE River or Sea Laid dug Crushed rocks

STORAGE OF AGGREGATE

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APPEARANCE Little evidence of origin face Some wear, faces reduced in size Little evidence of wear

Unlike cement, aggregate are deliver to site and damped in the open, the different size are being demarcated by partition or board. It is sometimes not advisable to use a lay 30-40mm layer to avoid or to protect it from intermingling and contamination by other materials. Therefore, it is best to put down 100mm minimum thick layer of concrete over the area where the aggregate will be stored, it is essential to provide substantial partitions to separate the different aggregates size and to prevent spillage from one bay to another. (Taylor, 1994) 2.7

GRADING OF AGGREGATE

Murdock et al (1979) stated that, aggregate varies in size from less than 0.1mm to 100mm. The largest size that can be used depends on the work to be done. The proportions of different size of aggregate will be in all mixes is known as grading. To find the grading of an aggregate, a sieve analysis must be carried out. The sieve sizes used for concrete aggregate are approximately 76mm, 38mm, 19mm, 9.5mm, 4.76mm, 2.38mm, 1.19mm, 595ụm, 297ụm, 145ụm, 74ụm. it is essential that amount used for sieving should be obtained from rather larger sample taken from the stockpile to ensure that the material tested is represented of the total.

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2.8

SIEVE OR SCREEN ANALYSIS OF FINE AND COARSE

AGGREGATE The purpose of this specification is to determine the particle size of fine and coarse aggregate to be used in various test. In this procedure, a weighted sample of dry aggregate is separated through a series of screen of progressively smaller opening for determination of particles size distribution. In this specification, the results are dependent upon individual technique. The test is placed in two categories mechanical sieving and hand sieving. This excellent test determine the gradation of the aggregate which is so important in mix design procedure. (Heins et al, 1981).

2.9

SAMPLING OF AGGREGATES

It is very important that nay sample of aggregate used for test purposes is truly representative of the bulk from which it is taken. This can usually be ensured by taking the sample in a number of increments from various position and levels in a stockpile, or bin and mixing them together. If this provides more materials than is needed, the sample may then be reduced by quartering that is, dividing it into four similar parts, rejecting two, which are

25

diametrically opposite and remixing the remaining two. An alternative to quartering is the use of a sample divider. Draw

“DIAGRAM HERE”

3.0

PROPERTIES OF AGGREGATE

The properties of aggregates include; i.

Bond

ii.

Strength

3.1

BOND OF AGGREGATE

Bond between aggregate and cement paste is an important factor in the strength of concrete, especially the flexural strength, the full role of bond being only now realized. Bond is due, in part, to the interlocking of the aggregate and the paste coming to the toughness of the surface of the former, a rougher surface, such as that of crushed particles, results in a better bond: better bond is also usually obtained with softer, porous and mineralogical heterogeneous particles. 26

3.2

STRENGTH OF AGGREGATE

Inadequate strength of aggregate represents a limiting case as the properties of aggregate have some influence on the strength of concrete even when the aggregate by itself is strong enough not to fracture prematurely. If we compare concrete made with different aggregates we can observe that the influence of aggregate in the strength of concrete is qualitatively the same whatever the mix proportions and is the same regardless of whether the concrete is tested in compression or in tension. In general, the strength and elasticity o aggregate depends on its composition, texture and structure. 3.3

OTHER MECHANICAL PROPERTIES OF AGGREGATE

Several mechanical properties of aggregate are of interest especially when the aggregate is to be used on road construction or is to be subjected to high wear. The first of there is toughness, which can be defined as the resistance of aggregate to failure by impact. In addition to strength and toughness, hardiness or resistance to wear is an important property of concrete used in roads and in floor surfaces subjected to heavy traffic. (Neville, 1978).

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3.4

REQUIRED CHARACTERISTICS OF GOOD AGGREGATE

i.

All aggregate should be inert in water and should not contain constituents that are liable to decompose or change in volume through exposure to the atmosphere.

ii.

Aggregate should be free from organic impurities which may affect the setting and hardening properties of concrete.

iii.

The particles should be free from coatings of dust or clay if the full bond is to be developed.

iv.

The compressive strength should be at least equal to that of developed by the cement paste which binds the particles of the aggregate together. Most natural aggregate are in fact much stronger than the much cement paste.

v.

Aggregate with a low absorption value must be used for all concrete that is exposed to the weather or is to be in contact with liquid. This requirement is particularly necessary in concrete to be used for liquid retaining or for reinforced concrete structures. A porous aggregate is liable to cause the concrete to spall under the action of

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frost. Special hard aggregate may have to be used in concrete exposed to severe wear. (IIein et al, 1977).

3.5

USED OF AGGREGATS

i.

Aggregates are used in making concrete

ii.

Aggregates are used as hardcore in flooring

iii.

Aggregates are used for rendering particularly when fine aggregate are mixed with binder.

iv.

Aggregates are used for block work, road work

3.6

IMPORTANCE OF AGGREGATES

Most concrete specification included a requirement for quality aggregates to ensure the quality of the hardened concrete, although poor quality natural sand may cause no deterioration under freeze/ than condition in air-entrained concrete. It causes significant variation in mortar shrinkage and water demand. Fine aggregate is used in concrete to improve the properties of the particle mix, facilitate finishing, promote uniformity and inhibit segregation, these improvement are accomplished largely by the grading size, shape and surface texture of the particle.

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3.7

SPECIAL AGGREGATES

i.

Low-density concrete; to decrease foundation loads, increase thermal insulation and reduce thermal inertia (light weight aggregate)

ii.

High density concrete: for example, as required for radiation shielding (baryles (bain sulphate) or iron- based aggregate.

iii.

Abrasion- resistant concrete for floor (granite or carbon random aggregate)

vi.

Decorative aggregate; for example, crushed granite is available in several different colour which can be revealed by use of an exposed aggregate finish (Taylor, 1974)

3.8

MOISTURE CONTENT

Since absorption represents the water contained in the aggregate in a saturated surface –dry condition, we can define the moisture content as the water in excess of the saturated and surface dry condition. Thus, the total water content of a moist aggregate is equal to the sum of absorption and moisture contents. Aggregate exposed to rain collects a considerable amount of moisture on the surface of the particle, and except at the surface of stockpiles, keeps this moisture over long periods. This is particularly true of fine aggregate and the 30

moisture content must be allowed for in the calculation of batch quantities and of the total water requirement of the mix. In effect, the mass of water added to the mix has to be decreased and the mass of aggregate must be increased by an amount equal to the mass of moisture content. Since the moisture content changes with weather and varies also from one stockpiles to another, the moisture content must be determined frequently (Brooks 1994) Also, the moisture condition of an aggregates is also important because this will affect the water content of the mix. This, in turn, affects the cement paste that binds the mass to produce strength. The amounts of water added to the concrete mixture should be adjusted for the moisture conditions of the aggregates in order to maintain the design water content. A large percentage of wet aggregate weight is actually water that will be added to the mix. Even aggregate that appears dry can add a significant amount of water to the mix. Since the water content is an extremely important indicator of concrete quality, determine the moisture content of the aggregate used and

adjust

the

batch

and

(hhtp://www.present.Org/pages/inc)

31

water

weight

accordingly.

3.9

EFFECTS OF MOISTURE CONTENT

Effects of moisture /water content in aggregate of concrete include; i.

WORKABILITY

Workability can be best defined as the amount of useful initial work necessary to produce full compaction. Presence of voids in concrete greatly reduces its strength 5% of voids can lower strength by as much as 30% and even 20% void can result in a drop of strength of more than 10 percent.

Therefore, the main factor affecting workability of water cement of the mix, expressed in kilogram of water per cubic metre of concrete it ought to be cohesive (Neville, 1981) ii.

STREGNTH

Strength of an aggregate product depends on the quality of the aggregates used. Also the amount of water presence in it and during mix. If not property measured can lower it strength. iii.

BLEEDING

Bleeding is known as water grain is a form of segregation in which some of the water in the mix tends to rise to the surface of freshly placed concrete. This is caused by inability of the solid constituents of the mix to hold all the mixing water when they settle downwards due to water content. 32

It can be expressed as quantitatively as the total settlement per unit height of concrete (Neville, 1981) vi.

ECONOMY

Economy refers to cost and is a direct function of proportioning. You can easily make concrete with varying amount of ingredient (cement, water, aggregate e.t.c) but each mix design will also vary in cost. Obviously, it’s ideal to make the most use of the cheapest ingredients and optimize the use of the most expensive. The water content in aggregate will require more cement, in order to make it workable. Therefore increase the cost.

4.0

HOW MOISTURE PENETRATE INTO THE AGGREGATE

Wilson (1984) recorded that, moisture is everywhere, present as an invisible gas and this is not quite as easily controlled. There is water vapour in the air all around us. It seeps into the cavities of construction assemblies in stud and joist cavities, into the cores of mansory units. Absorbed water is present in most construction assemblies and determines their dimensional characteristics vapor moisture is not damaging, however it is a fickle gas changeable, and becomes dangerous as it condenses liquefies,

33

and freezes, condensation hidden over a period of time in building assembles can cause spalling of aggregates (concrete) and mansory. Also, rain contribute greatly to these moisture content which can be as high as 12-15%. FIG 11. DIAGRAM REPRESENTATION OF MOISTURE IN AGGREGATE

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4.1

SAND

Taylor (1990) Stated that: sand is a fine aggregate formed by the natural disintegration of rock, or it is artificially created by crushing stone or gravel to the required sizes. Only small amounts of crushed stone sand are used in plastering industry, its use being confined to special cement work on the whole. Natural sand has been formed over the centuries by the action of wind, rain, forest and running water to break down rocks into small particles. These small grains, varying in size, have been washed by the action of the seas and rivers and deposited in certain areas which have in turn been moved inland due to past changes of the earth’s formation. This is the reason for large pockets or deposits of sand many miles inland. The two main types of sand available at present are pit sand from inland quarries and river sand obtained by dredging. Sea sand is unsuitable because of the risk of effloresces due to the presence of salt. Crushed stone of ten contain too much fines. A good sand should contain a suitable proportion of large, medium and small grains. The reason for this can be seen below.

35

FIG 111: SKETCH OF A SAMPLE OF SAND

36

If the sand is composed of large particles only, then there will be many spaces or voids between the grains. This type of sand would require a lot of cement to make a strong, dense mix. As a result the mix would be expensive because of extra shrinkage would not be strong enough. A well graded sand has medium sized grain to fill in the layer avoids and small sized grains to fill in the smaller voids. The functions of sand are: 1.

To induce mix to shrink uniformly during the process of setting and hardening irregular shrinkage being a general cause of cracking.

2.

To lower the cost of the mixed material providing the biggest bulk of the mix.

3.

To assist workability, particularly on thicker application such as floating coats.

4.2

BULKING OF SAND

In the case of sand, there is another effect of the presence of moisture, viz bulking, which is an increase in the volume of a given mass of sand caused by the films of water pushing the sand particles apart. While bulking per does not affect the proportioning of materials by mass in case of volume batching bulking result in a smaller mass of sand occupying the fixed

37

volume of the meaning box. Volume batching represents bad practice, and no more than the proceeding warning in needed. Water present in sand can affect mix proportion in a second way. Damps sand takes up a layer volume than does dry or completely saturated sand. Moisture contents of about 6 percent can ensure an increase in volume, known as bulking of up to 30 percent. This means that if sand is batched by volume there can be considerable variation in weight. A simple method in used to find the percentage bulking which utilize the facts that dry sand saturated and here the same volume. Damp sand is packed n a large measuring cylinder and its volume found. This is then emptied out so that some water may be added then replace gradually to saturate it. The new sand volume is found. Percentage bulking = Vw – Vs x 100 Vs Where Vw = volume of moist sand Vs = volume of saturated sand (Neville, 1981)

38

4.2

BULKING OF COARSE AGGREGATE

Coarse aggregate shows only a negligible increase volume due to the presence of free water, as the thickness of moisture film is vary small compared with the particle size. 4.3

FIG IV: RANGE OF MOISTURE AS THEY AFFECT

AGGREGATE STATE.

4.5

ABSORPTION AND SURFACE MOISUTE The following terms below should be clearly understood

i.

Air dry: Dry at the surface though containing some interior moisture, but less than the amount required to saturate the particles. In this condition an aggregate can absorb more water into itself, and may still 39

appear dry on the surface. But absorbed moisture plays no part in the lubrication of mixed concrete. ii.

OVEN DRY: Completely dry for practical purposes

iii.

WET: The aggregates is itself saturated and carries an excess of moisture forming film on the surface of the particles. The absorption of different particles size of the not necessarily be taken as representatives of the aggregate through the whole range of grading.

Since movement of moisture in the aggregate due to raining or change in temperature which changes the length of aggregate at different stock piles or locations (Brook, 1979) 4.6

MEASUREMENT OF MOISTURE CONTENT

The moisture content of aggregate is of vital importance on the control of concrete worktability, strength and quality. The measurement of the moisture content of aggregate is basically a very simple operation but it is complicated by several factors. The aggregates will absorb a quantity of water depending on its type and then the water content can be quoted in terms of the weighted of aggregates when absolutely dry, surface dry and when wet. The water content can be free water content, or that held on the surface of the aggregates, or the total water content which includes the absorbed water plus the free water. The specific gravity and 40

absorption of an aggregate depends also to some extent on its particle size and this fact should be borne in mind when planning tests. For fields use the method adopted must be quick, reasonably accurate, and must need only simple apparatus which can easily be replaced damaged. There are large numbers of different method of making the determination of which are include. i.

Drying method The aggregates before and after drying. Drying can be effected; a. In an oven at a temperature of between 1000 and 1100c b. In an open pan over a heater c. By pouring over the aggregate an inflammable liquid which is miscible with water and igniting it, methylated spirits and acetone are suitable for this purpose.

41

4.7

CONTROL OF AGGREGATE FROM MOSITURE ON SITE Aggregate should be stores, so that they are kept as uniform as

possible in grading and moisture content, also protect it from interminingling and contamination by other materials. Therefore, its is best to put down a 100mm minimum thick layer of concrete over the areas where the aggregate will be store; concrete should be laid to fall away from the mixer to facilitate free drainage of water from the aggregate. And should extend well out from the mixer set-up so that all deliveries can be tipped onto it. -

It is essential to provide substantial partitions to separate the different aggregate sizes and to prevent spillage from one sand to another.

-

Variation effects, which commonly occur in moisture content of fine aggregate, will need adjustment to the water/cement ratio control.

-

Variation in the moisture content of coarse aggregate as delivered, or in the stockpiles, are usually not sufficient to have much effect on the control of water/cement ratio.

-

When fine aggregate is very wet, so sometime happen with fresh deliveries, or after it has been raining, the moisture content can be as high 12-15%. Therefore, adjustments are made to the water added at

42

the mixer excessive variation in workability and strength and durability will result (Black ledge, 1990)

4.8

WOOD

Wood has been an important construction material since humans began building shelters, houses e.t.c A very high proportion of house in the united kingdom are of partly timber frame construction. The word timber describes wood that has been cut for use in building. Timber has many advantages as a building material. It is a light weight material that is easy to cut, shape and join by relatively cheap and simple hand or power operated tools in protection of walls, floors, and joinery generally. As a structural material it has favourable weight to modulus of elasticity ratios and coefficients of thermal expansion, k valves, density and specific heat, with adequate sensible selection, fabrication and fixing and adequate protection it is a reasonable durably material in relation to the life of most building. Softwoods and hardwood are term used to classify different timber. The very majority of our homes have the roof construction of wood the floors both at the ground and above are constructed of woods the floor both

43

at the ground and above are constructed of woods together with doors, window, frames and skirting boards. As time goes by wood became more costly; the higher standard of living demanded by people throughout the world means that the cost of extracting the logs from the forest, their transport, conversion to timber and fabrication into desired shapes and distribution to the customers is progressively more costly. In addition to this, the more accessible forest have long since been cut, so that sizable timber must be sought for in remote areas. Replanting programmes have not always been undertaken. This makes conservation of existing timber in our building of prime important. Engineered wood product are becoming a bigger part of the construction industry. They may be used in both residential and commercial building as such structural and aesthetic materials.

4.9

WOOD PROPERTIES

some types of wood are very hard and durable and some are flexible enouh to bebent. “hardwood” is the one of the common types of woods. This is obtained from trees that lose their leaves in winter. The other type of wood, the “softwood” is aobtained frin evergreen trees like fir,pine and redwood. All the woods fall between a range from very soft to very hard. 44

All type wood have distinctive grain structure. Wodds like white abd red oak, ash and walnut havbeopen-pores in the form of small hole on their surface that give a distinct textural quality to furniture piece like wooden cupboard or wooden desks. When thw surface of this wood is stained, the colour tends to collect in the “open-pores” abd apper darker than the rest of the piece. There are other woods. These woods are have the smooth texture and can take finish evenly. Apart from grains, one more characteristic of many woods is unique figure on their surface such as quilting, birdseye, fiddleback and spalting. These naturally occurring characteristics can make a furniture acquire extraordinary beauty.

5.0

Hardwoods

Mahogany: is finely grained wood with reddish brown colour. It is highly durable and can resist swelling, shrinkage and warping. It is extensively used for quality furniture such as wooden cabinets, boat construction, wood facings and veneers. Walnut: has fine texture and is strong, easy to work with. It resists shrinkage and warping and can take all types of finishes very well. It is mostly used for making gunstocks, solid and veneered furniture, novelties, cabinetry and wall paneling. 45

Oak: has good bending quality apart from being durable. It finishes well and resists moisture absorption. Oak is good for furniture, trimming, boat framing, wooden desks and flooring. Maple: is a fine textured wood with immense strength and hardness. With moderate shrinkage, maple machines well and is best in flooring, fine furniture and woodenware such as bowling alleys. Cherry: is close-grained wood and as resists warping and shrinking. It gets red when exposed to sunlight. It ages well and is extensively used in cabinet making, boat trim, novelties and solid furniture handles. Rosewood: is close grained hard wood with dark reddish brown Color. It has an exclusive fragrance. It is hard to work upon and takes high polish. It is good for making musical instruments, piano cases, tool handles, art projects, veneers and furniture. Teak: is a hard and moisture-resistant wood. It resists warping, cracking and decay and is best used in fine furniture, paneling, shipbuilding, doors, window framing, and as a general construction wood. Shesham: is also known as Indian rosewood and is rich medium brown wood with deep grains. It is a fast-growing hardwoods and the functional furniture made from it can deal with everyday stresses and strains without

46

loosing its attractive appearance. It is highly durable, easily carved and is exclusively used for making furniture, particularly almirahs and cabinets.

5.1 Softwoods Pine: has a uniform texture and is very easy to work with. It finishes well and resists shrinkage, swelling and warping. It is widely used in house construction, paneling, furniture, molding and for making wooden boxes. Hemlock: is lightweight and machines well. It is uniform textured and has low resistance to decay. It is mainly used for construction, Lumber, planks, doors, boards, paneling, sub flooring and crates. Fir: is uniformly textured and has low resistance to decay. It is nonresinous, works easy and finishes well. Fir is used for making furniture, doors, frames, windows, plywood, veneer, general millwork and interior trim. Redwood: is light, durable and easy to work with. It has natural resistance to decay and is good for making outdoor furniture, fencing, house siding, interior finishing, veneering and paneling. Spruce: is a strong wood that finishes well and has low resistance to decay. It possesses moderate shrinkage and light. It is good option for making

47

masts and spars for ships, aircraft, crates, boxes, general millwork and ladders. Cedar: is a reddish wood with sweet odor. It is very easy to work with, uniform in texture and is resistant to decay. Cedar is extensively used in chest making, closet lining, shingles, posts dock planks, novelties and venation blinds. The structure and composition of wood The virtues of wood – it high strength to weight ratio ease of working with tools and machines, its insulating and sound absorbing properties, resistance to chemical and its inherent beauty, all reflect its structure and chemical composition. Yet one of the main disadvantages of wood its susceptibility to decay, is also a feature of that same structure and composition

5.2 Types of wood The timber are divided into groups -

hardwoods are timber converted from trees bearing flowers (angiosperm) whereas

-

Softwood are timber converted from the Gymnosperm, almost all belong to the conifer. 48

Most of the species in the second group bear cones and needle-shaped leaves. It will be seen therefore, that hardwood and softwood are technical terms having an exact meaning although the hardwood are usually hard and the softwood are soft, this is not invariable the case. Some species of hardwoods are relatively soft (e.g. Balsa) In building, softwood is by far the most important type of timber used for construction and crevassing purposes, on a gross tonnage basis. Hardwood have traditional been used for joinery and floors which are to undergo heavy wear and their decoration properties have also influence their use in these situations.

5.3 Moisture in wood The moisture content of wood i.e. the amount it contains substantially influences it physical and mechanical properties and in many cases determine its suitability for one purpose or another. Water contained in wood partially fills internal voids, i.e. the vessel canal the cavities in the cells and the intercellular spaces, anal is known as the free moisture, and partly saturates the cell walls and called the hygroscopic (to absorb moisture from the air) or bound moistures. The bound moisture occupies the intercellular space and is partly in colloidal linkage with a substance of 49

wood. The free and the hygroscopic can be removed from the wood by drying. The chemical bound moisture, entering into the composition of the matter forming the wood, can only be removed by chemical reaction. The maximum amount of hygroscopic moisture to about 30% at a temperature of 20*: at this moisture content, known as the cell wall saturation point or fibre saturation point, the moisture completely saturate the cell walls and any future increase in moisture content can only take place through the free moisture. i.e. by filling the voids in the wood. The fibre saturation point is the limit of hygroscopic, as it corresponds to the maximum amount of moisture Which can be taken up by wood which can be taken up by wood when keep in air saturated with water vapour. As moisture contents is varied from zero to the fibre saturation point both the volume and the linear dimension of wood change. The increase in moisture content within the indicated limit is accompanies by the phenomena swelling and a reduction by shrinkage. The reason for the contraction of wood when it is dried is the removal of water from the intestacies between the chain molecule of cellulose and hemicelluloses when consequently approach one another. The opposite effect is called swelling contraction during the dry and swelling, during damping the fibres always takes in a transverse direction and not observed 50

for the length. The den the wood i.e the higher its bulk density, the more shrinkage and swells. When moisture content is increased beyond the fibre saturation point, and the water begins to occupy the voids of the cells, there is no further swelling. Freshly cut timber contain 80-100% of moisture, while in softwoods the moisture content of sapwood is 2-3times greater than that of the heartwood. The moisture content of floated or refted timber can be high as 200%.

5.4 Influence of moisture content It is necessary to specify that there shall be a certain amount of water, and no more or less, in timber suitable for building. Moisture content is stated as a percentage of the dry weight of the timber. The dry weight of any piece of timber is its weight after it has been so dried that further drying causes it to lose no more weight. This dry weight is reasonably constant for a given cubic measure of each type of wood and is used as constant against which the moisture content can be assessed. The moisture content of timber should be such that timber will not appreciably gain or lose moisture in the position in which it is fixed in a building. Control of moisture in wood

51

Natural drying seasoning: This is when logs have been cut into timbers they are stacked either in the open or in a rough open sided shed. The timbers are stack with battens between them to allow air to circulate around them. Timbers are left for several year until most of the moisture in the wood has evaporated. Artificial or kiln seasoning: As a result of great length of time required for natural drying method and because sufficient low moisture content of wood cannot be achieved, artificial method is largely used. This when the wood has been converted to timber and they are placed in the enclosed kiln. Air is blown through the kiln, the temperature and humidity is being regulated to effect to drying more rapidly, but not so rapid as to cause damage to the timber. Moisture in wood can be best control by storing them in a shed, this will reduce the their level of exposure to rainfall, dew e.t.c. It can be sun dried naturally or with the use of natural air or use of industrial fan. 5.5

Brick /Block

Bricks are blocks of clay that have been hardened through being fired in a kiln or dried in the sun. over time, kiln-fired bricks have grown more popular than sum-dried bricks, although both are still found worldwide. 52

Bricks have been in continual use for around 5000years, and brickwork from this time still stands in the Middle East, a testament to its durability. The Roman Legions first brought bricks to Britain, using mobile kilns to construct roads, aqueducts and buildings across the country. Bricks were especially favoured in the 18th and 19th Centuries, although their use has declined over the last 50 years due to the increased availability of cement and concrete.

5.6 Manufacture of Bricks In the past, bricks came in many different shapes and sizes, but today’s modern bricks tend to be a standard size of around 8” x 4’’ x 2’’. They demonstrate a wide variety of textures, colours and finishes from yellows, reds and purples, to smooth, rough and rustic. These are due to the mineral variations found in the clay, and the method of manufacturing. Bricks are traditionally manufactured by mixing clay with enough water to form a mud that is then poured into a mould of the desired shape and size, and hardened through fire or sun. Adobe bricks, very fashionable in parts of the USA, are still made in this way with a mixture of clay and sand (and sometimes manure and straw) being poured into a form, and then removed and dried in stacks outside in the sun. 53

Compressed Earth Blocks (CEBs) were developed in the 1950s and are similar to adobe bricks, except they are more compact and uniform. They are manufactured from soil that is more sand than clay, and compressed using a manual or motorized machine to produce a variety of block shapes, including hollow designs for insulation. CEBs are highly energy efficient using up to 15 times less energy than a fired brick. They are durable, ecological, inexpensive, and utilize low technology. For this reason they are increasingly used in developing countries as a sustainable building technology. Modern methods of brick manufacture are highly mechanized and automated procedures whereby clay is extruded in a continuous column, wire cut into bricks, and hydraulically pressed to ensure resistance to weathering. The bricks are then dried and slow fired at around 1000-1200oC. In more recent times, recycled glass and other waste materials have been introduced into this process. These materials have been found to reduce firing times, temperatures and toxic emissions, improve brick strength and durability, and reduce waste going to landfill.

54

5.7 Brick Laying Bricks are laid flat in rows called courses, exposing either their sides (stretcher) or ends (header). The pattern of overlap created by the course is called a bond. There are several different kinds of bonds, including stretcher (most common), Herringbone, English, Basket and Flemish. With all bonds, the vertical joints between each course of bricks must not line up or the structure will be warkened. Bricks are usually held together by mortar, though some bricks such as CEBs can be dry stacked. Mortar consists of sand, a binding agent (traditionally lime but these days more often cement) and water, which is then mixed to a thick paste. It is applied to a brick, which is then placed onto another brick and allowed to dry. Pointing refers to the visible edge of the mortar between the bricks, which is finished with a special trowel to provide a decorative look to the brickwork. When building a structure, a bed of mortar is laid on top of the foundation, and the structure’s ends are built up first. A string is then stretched between these ends to ensure each row of bricks stays level. Two layers of brick are used to create a stronger structure, with a gap left in between for insulation 55

purposes. A wide range of structures including arches can be built using bricks. Bricks as a Sustainable Building Material. Bricks are a versatile and durable building and construction material, with good load-bearing properties, high thermal mass and potential low energy impact. In the case of simple earth bricks such as adobe and CEBs, they measure high on the sustainability index, being made from locally available (and abundant) materials, of clay, sand, and water, using low technology compression equipment, solar energy or kilns. While modern methods of bricks construction have a much lower sustainability index, the UK brick industry has developed a strategy to minimize its environmental impact and increase its energy efficiency and use of renewable energies. Overall, bricks are a good example of a sustainable building practice and are currently gaining in popularly around the world. Moisture absorption The amount of water a brick will absorb is a guide to its density and therefore its strength in resisting crushing. The level of water absorption is most critical for brick to be used. Absorption rates vary between 1% and 35%.

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CHAPTER THREE 3.0

RESEARCH METHODOLOGY

3.1

This chapter of the project involves the processes engaged in carrying

out the practical/experiment and collection of result to provide solution to research question. 3.2

POPULATION FOR THE SAMPLE

The population of the practical for this research concentrate on moisture determination on construction material. These materials; fine aggregate coarse aggregate, various types of wood and brick were used, for the project for the purpose of construction work. 3.3

SAMPLES

The samples for this project were measured weight as stated. 20kg of fine aggregate and. 32kg of 10mm coarse aggregate taken to the laboratory wood. 200mm x 600mm Mariana (softwood) 200mm x 600mm Itara (hardwood) 200mm x 600mm Arere (softwood) 200mm x 600mm Parana (softwood) 57

200mm x 600mm Eku (Hard wood) 200mm x 600mm Balsa (Hard wood) 3.4

SAMPLE SELECTED

Sample selected for this test were obtained from more than one location. The aggregate samples used are natural pit gravel, natural coarse aggregate and crushed granite. Each sample were mixed together to distribute evenly for the test. Also test were conducted on different types of wood (Hard and soft wood). The types of wood tested includes: Mariana (softwood), itara (hardwood), Arere (softwood), Parana(softwood), Eku (hardwood), Balsa(Hardwood), mahogany(hardwood). And also Brick/block.

3.5

MOISTURE CONTENT TEST

Drying method was used to determine the moisture content of all the samples listed above, that is, the mass the ratio of the weight of water to the weight of dry sample of the materials to be tested.

Moisture content (M.C) = Weight of water

x 100.

Weight of sample

58

3.6

USED APPARATUS • Digital balance

•

Drying can

• Scoop

•

3.7

Drying oven DRYING METHOD

This method was adopted through out this project to determine the content of the listed samples. FOR AGGREGATE The specimen for the test was kept in polythene bag to avoid equilibrium moisture content in the laboratory. And the sample was weight after mixing the material to distribute the moisture evenly. The sample was oven dried for 59

2hours (start time: 3:55 p.m, stop time 5:55 p.m) with constant temperature of 105*C, after which the weight of the dried sample was obtained. The method of calculation used is thus: Moisture loss= (container + wet sample) - (container + dry sample) Dry sample= (container + dry sample) – (container empty) Wood test was performed. Thee initial weight of the woods were measured and recorded, after it was oven dried and also measured to determine the moisture content. The method of calculation used is thus: Moisture content = Weight when cut – Oven dry weight x 100 Oven dry weight The same was done on brick. 3.8

METHOD DATA ANALYSIS

The data collected from laboratory practical work will be represented in tabular form.

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CHAPTER FOUR 4.0

ANALYSIS OF DATA AND DISCUSSION OF RESULTS

4.1

MOISTURE CONTENT TEST

The result of moisture content using drying method only. 4.2

DRYING METHOD

The result of the moisture content for all the samples used are shown in the table below. TABLE 1: AGGREGATE MOISTURE CONTENT DETERMINATION MOISTURE CONTENT IN AGGREGATE DETERMINATION

FINE

NATURAL

CRUSHED

SIMPLE Container + wet sand Container + dry sand Empty container Dry sand Moisture loss Moisture content

AGGREGATE 56.1 52.1 16.1 36.0 4.0 11.1%

GRANITE 55.0g 50.0 5.0 45g 5.0 11.1%

GRANITE 50g 45.0 5.0 40g 5.0 12.5%

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TABLE 2: MOISTURE CONTENT IN WOOD (TIMBER) WOOD TYPES

MOISTURE DRY INITIAL

Maniana

WEIGHT soft 40g

wood Itara-hard wood Arere soft wood Paranan wood Eku Hard wood Balsa(Hardwood), Mahogamy hard

30.0 20.0 20.0 40.0 45.0 35.0

MOISTURE MOISTURE

WEIGHT LOSS

CONTENT

35.0

5.0

14.3%

28.0 18.0 16.0 35.0 40.0 30.0

2.0 2.0 4.0 5.0 5.0 5.0

6.7% 10.0% 20% 12.0% 11.1% 14.3%

wood TABLE 3: MOISTURE CONTENT IN BRICK DETERMINATION SIMPLE Brick + moisture (initial weight) Dry brick Moisture loss Moisture content

4.3.

READINGS 365g 355 10.0 2.8%

FINDINGS/RESULTS

From table 1, the result shows that the moisture content of natural pit sand, natural granite to be 11.1%, 11.1% and 12.5 respectively. 62

From table 2, mariana (softwood), Itara (hardwood), Arere (softwood), parana (softwood), eku (hardwood), Balsa (hardwood), mahogany (hardwood) to be 14.3%, 6.7%, 10.0%, 20.0%, 12.0%, 11.1% and 14.3%. From table 3, Brick shows moisture content of 2.8% 4.4

DISCUSSION OF RESULTS

From the result or data obtained it can be deducted from the tables  The method of drying which must have ensured an accurate dry weight  The quantity of aggregate used which was 0.5kg since adequate

balance was used for the weighting of the sample tested.  It was discovered from table 1 that granite has different moisture

content, for instance natural pit granite and crushed granite.  It was of observed that moisture content varies in wood in respective

to the type of the wood.

CHAPTER FIVE 5.0

CONCLUSION AND RECOMMENDATION

5.1

CONCLUSION 63

To conclude this research work various methods was carried out for determination of moisture content of aggregates, wood and bricks used on construction sites. The purpose of measuring the moisture content of aggregate is to enable an estimate to be made of the quantity of water contained within so that the water added to concrete can be adjusted. Considering the determination of moisture in wood, this is done in order to increase the quality of article made from it. From research it was gotten that moisture in wood should be higher then range of 20% or 25% for dense hardwood and 15% or 20% for softwood and low density hardwood. Minimum moisture content of thoroughly dried is 10% to 15%.

5.2.

RECOMMENDATION

Since the significance of this study is to reveal to users and students the procedure of measurement and control of moisture of aggregates to produce good quality concrete. The followings are recommended: Freshly delivery aggregate, especially fine aggregate during raining season should be left unused after 24hours of delivery before use so that some of the water it contained may be drained off before use.

64

The moisture content of aggregate delivered to the site for construction purpose must be determined before it is used for any construction work to regulate water content. It is best to put down a 100mm minimum thick layer of concrete over the areas where the aggregate will be stored so that risen of moisture from the soil could be avoided and to protect aggregate from intermingling and contamination by other materials Wood should be installed at moisture content levels as close as possible to the average moisture it will experience in service. This minimizes the seasonal variation in moisture content and dimension after installation, avoiding problems such as floor bucking or cracks in furniture. Brick must be adequately dried to the required or standard level of moisture that is required to be present before construction proper. Brick should be stored appropriately after casting under regular weather condition.

5.4

SUGGESTION FOR FURTHER STUDIES

65

Based on findings, moisture, content can also be further study using other method of determination /measurement. I suggest that the following methods should be also examined. i.

Sipon-can method.

ii.

Speedy method.

iii.

Pycnometer method.

REFERENCES 66

BLACKLEDGE, G.F (1990) concrete practice. Britain: British Cement Association. BROOK, K.M & MURDOCK, L.J (1978): Concrete material and practice London: Edward Arnold (publisher) BROOK, J.J & NEVILLE, A.M (1994): Concrete Technology London: Singapore: Longman Singapore publisher Limited DERNCHER, K.N & HEINS, C.P (1981): Materials for Civil and Highway Engineers U.S.A: Prentice Hall, inc. England clifts. NEVILLE, A.M (1981): Properties of concrete (3rd Edition) London: Pitman Publishing Limited. ORCHARD, D.F (1990): Concrete Technology (vol 3) P [properties and Testing of Aggregates. London: Applied Science Publisher Limited. SMITH, B.J (1978): Construction Science (volume 2). New York: Longman Inc. TAYLOR, J.B (1990): Plastering fifth Edition. England: Addison Wesley Longman Limited. TAYLOR, G.D (1994): Material in construction (2nd Edition). London Longman Singapore Publisher (pte) limited.

67

WILSON, F. (1984): Building Material Evaluation Handbook. NEW York: van nostrand Renhold Company Inc.

68

APPENDIX

Natural pit sand sample

Natural pit sand sample

69

Coarse aggregate sample

70

Parana(softwood)

Itare (Hardwood)

71

72

Arere(softwood

Eku( Hardwood)

Balsa (hardwood) 73

Mahogany (hard wood)

Mariana (softwood)

74

Brick Sample.

75