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The Effect Of Admixtures On Properties Of Co`ncrete
[CASE STUDIES OF SUGAR, COW BONE ASH, GROUDNUT SHELL ASH, AND LIME STONE POWDER]
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Roberto el at (1996) describes aggregate physical properties as the most readily apparent properties and they also have the most direct effect on how the aggregate performs as either a pavement material constituent or by itself as base sub base material.
Roberto further said aggregate as voids, and there are voids between aggregate particles. As solid as aggregate maybe for the naked eyes, most aggregate as voids which are natural pores that are filled with air or water. These voids or pores influence the specific gravity and absorption of the aggregate material.
Examples of aggregate are:
i. Gravel: They are granular substance predominantly retained in 4.75mm sieve and resulting from material disintegration and abrasion of rock or processing of weekly bound conglomerate.
ii. Sand: Are granular material passing through the 4.75mm sieve and predominantly retained in 75mm sieve, and resulting from natural disintegration and abrasion of rock or processing of completely friable sandstone.
iii. Crushed Stone: The product result from the artificial crushing of rocks, boulders or large cobble – stone, substantially all faces of which have resulted from the crushing operation.
iv. Air Cooled Blast-Furnce Slag: This is a material resulting from the solidification of molten blast – furnace slag under atmospheric conditions. Subsequent cooling may be accelerated by the application of water to the solidified surface.
v. Crushed Gravel: This is a product resulting from the artificial crushing of gravel with substantially all fragments having at least on face resulting from fracture.
2.4.2 Cement
Salami (2002), said cement can be describe as a material with adhesive and cohesive property which bind together the particles of aggregate usually sand and granites to form a mass of high compressive strength known as concrete.
Cement cannot be shown by a chemical formula as it is complex mixture of several compounds. However, there are four compound computed from the oxide analysis of cement that for all practical purpose may be considered as comprising the cement. The main compounds with their commonly accepted abbreviation are
Tricalcium silicate = C3S
Dicalcium silicate = C2S
Tricalcium silicate = C3A
These compounds as they called are not true compounds in the chemical sense but the computed proportions of these compounds reveal valuable information concerning the cement strength – developing characteristics of cement depend on the C3S and C2S which comprises about 75% of the cement. The C3S hardens rapidly and therefore has a major influence on setting time and early strength; hence a high proportion of C3S result in high early strength and high heat hydration C2S on the other hand hydrates more slowly and contributes to strength gain, C3A contributes to high early strength and high heat but result in undesirable properties of concrete, such as poor sulphate resistance and volume change.
2.4.2.1 Physical Properties Of Cement
i. Fineness: Is the sub division of substances. The rate of hydration of cement depends on the fineness of cement particles, and for a rapid development of strength high fineness is necessary. Achievement of fineness is carried out at the final step of manufacturing cement, where clinker is grinded with gypsum. Cement particles because it is smaller in size it cannot be separated by using sieve and other method of measuring particles size. The specific method is commonly used in which the particles of cement of cement are considered to be spheres. The specific surface is the summation of the surface area in square centimeter of the particles in l gram of cement.
The Wagner turbidimeter is based on the principle that turbidity is a measure of the surface area of a sample of cement. Turbidity is determined at interval by measuring with photoelectric cell.
ii. Setting Time: setting is the term used to describe stiffness of cement paste. The beginning of noticeable stiffening in cement paste is known as initial setting. Further stiffening in cement occurs as the volume get increases and the stage at which this is complete called final set. It is grouped into two;
iii. Flash Set: It is immediate stiffening in cement. It takes place in cement with insufficient gypsum to control the rapid reaction of C3S with H2O. These reactions generate a considerable amount of heat and cause the cement to stiffen in few minutes after mixing. This can only be overcome by adding more water and regulate the mix.
iv. Flash Setting: A false setting also produces a stiffening of paste but not accompanied by excessive heat. In this case remixing the paste by not further addition of water causes it to regain its plasticity and its subsequent setting and hardening characteristic are quite normal.
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ABSRACT - [ Total Page(s): 1 ]ABSTRACT The project titled “The effect of admixtures on properties of concrete: case study of sugar, cow bone ash, groundnut shell ash, and lime stone powder†was carried out with the aim of knowing the effect the of the various types of admixtures used on the properties of concrete, in term of the workability of concrete, durability of concrete and the concrete strength. The material used are cow bone ash, groundnut shell ash, sugar and lime stone powder. The cow bone was sou ... Continue reading---
LIST OF TABLES - [ Total Page(s): 1 ]LIST OF TABLESTable 4.1: Data Analysis for Fine Aggregates (Sand) Table 4.2: Data Analysis for Coarse Aggregate (Granite) Table 4.3: Slump Test Result for GSA Concrete Table 4.4: Slump Test Result for CBA Concrete Table 4.5: Slump Test Result for Sugar Concrete Table 4.6: Slump Test Result for LP Concrete Table 4.7: Summary of Slump Test Result for Various Concrete Admixtures Table 4.8: Compressive Strength Test Result of Normal Concrete Table 4.9: Compressive Strength Test ... Continue reading---
LIST OF PLATES - [ Total Page(s): 1 ]LIST OF PLATESPlate 3.1: Groundnut Shell and Cow Bone Plate 3.2: Burning of Groundnut Shell and Cow Bone Plate 3.3: Cow bone ash, Groundnut shell ash, Limestone powder and Sugar. Plate 3.4: Batching of Concrete Plate 3.5: Type of Slump Plate 36: Cube Production Plate 3.7: Curing of Cubes Plate 3.8: Crushing Machine ... Continue reading---
LIST OF FIGURES - [ Total Page(s): 1 ]LIST OF FIGURESFigure 4.1: The graph of sieve analysis for Fine Aggregate (Sand) Figure 4.2: The graph of sieve analysis for Coarse Aggregate (Granite). Figure 4.3: The graph of slump test result for GSA Concrete Figure 4.4: The graph of slump test result for CBA Concrete Figure 4.5: The graph of slump test result for SUGAR Concrete Figure 4.6: The graph of slump test result for LP Concrete Figure 4.7: The graph for summary of slump test result for various Concrete AdmixturesFigure 4.8: Th ... Continue reading---
TABLE OF CONTENTS - [ Total Page(s): 1 ]TABLE OF CONTENTSTitle Page Declaration Certification Dedication Acknowledgement Abstract Table of Contents List of Tables List of Figures List of Plates CHAPTER ONE 1.0 Introduction 1.1 Statement of the Problem 1.2 Aims and Objectives of the Study 1.3 Justification of the Study 1.4 Scope of the Study CHAPTER TWO 2.0 literature Review 2.1 Concrete ... Continue reading---
CHAPTER ONE - [ Total Page(s): 2 ]CHAPTER ONE1.0. INTRODUCTION The importance of understanding various types of materials used in Civil Engineering is widely recognized. There has been tremendous increase in the latest research and practical achievement to improve on concrete technology. Free exchange for technical know ... Continue reading---
CHAPTER THREE - [ Total Page(s): 8 ]CHAPTER THREE3.0 PROJECT METHODOLOGY For successful accomplishment of the aims and objectives of this project the following methods are applied.i. Market survey for the most commonly used cement was carried out and it was found that elephant and dangote cement are the most commonly used in the locality due to their availability in the market all time.ii. Text books, internet and some experienced practicing engineer are consulted in order to obtain relevant and detailed ... Continue reading---
CHAPTER FOUR - [ Total Page(s): 16 ]D10 = 1.686μmm = 0.169mmD30 = 273.6μmm = 0.274mmD60 = 503.75μmm =0.504mmi. The effective grain size; i.e. D10 = 0.169mmii. Uniformity coefficient, Cu = = = 2.98iii. Coefficient of curvature, Cc = = = = 0.88D10 = 7.6mmD30 = 12.8mm D60 = 15.2mmi. The effective grain size; i.e. D10 = 7.6mm ii. Uniformity coefficient, Cu = = = 2.0iii. Coefficient of curvature, Cc = = = =1.42 ... Continue reading---
CHAPTER FIVE - [ Total Page(s): 1 ]CHAPTER FIVE5.0 CONCLUSION Based on the results of this investigation, the following conclusion is drawn; Admixtures affect properties of concrete like its slump value, density, compressive strength, etc. Admixtures generally decrease the slump value of concrete which in turns decrease the workability of the concrete, since normal concrete(0% concrete) has a slump value of between 55-60mm while concrete with admixture has slump value lesser ... Continue reading---
REFRENCES - [ Total Page(s): 1 ]REFERENCEAkogu Elijah Abalaka (2011): ‘Effects of Sugar on Physical Properties of Ordinary Portland Cement Paste and Concrete.Albadan B.A, M.A Olutoye, M.S Abolarin & M. Zakariya (2005): ‘Partial Replacement of Ordinary Portland Cement (OPC)with Bambara Groundnut Shell Ash (BGSA) in Concrete. Leonard Electronic Journal of Practices and Technologies. Issues 6, pp. 43 – 48, January – June 2005. Aribisala, O.J & Bamisaye, A.J (2006): ‘Via ... Continue reading---
