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The Effect Of Water/cement Ratio On Compressive Strength Of Palm Kernel Shell Concrete At 1:2:4 Nominal Mix
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3.2.6 Compressive strength test
Compression test is the most common test on hardened concrete, partly because it is an easy test to perform and partly because most of the desirable characteristic properties of concrete are quality related to its compressive strength.
The compressive strength of concrete is most common performance measure used by the engineer in designing and other structures. The compressive is measured by breaking concrete cubes of cylindrical concrete specimens in a Compression Testing Machine. The compressive strength is calculated from the failure load divided by the cross- sectional area resisting the load. The value of compressive strength can then be used to assess whether the batch that the concrete cube represents meets the required compressive strength.
The compression test results can be used for quality control, acceptance of concrete or for estimating the concrete strength in a structure for the purpose of scheduling construction operation.
For this research, the compressive strength results are used to determine whether palm kernel shell concrete can be classified as lightweight concrete (LWC).
Compressive Strength = (Crushing load (N))/(Effective Area (〖mm〗^2 ) ) N/mm2
3.2.7 Determining the Weight of the Concrete Composite
During the course of performing this experiment “batch by volume†method was incorporated. The procedure used in determining the volume of materials to be used is shown below;
X/1000+CEMENT/(G_C*1000)+(2 SAND )/(G_S*1000)+4PKS/(G_PKS*1000)=1m3
Where X= 0.3, 04, 0.5, 0.6, 0.7
GC= Specific Gravity of Cement = 3.15
GS =Specific Gravity of Sand = 1.37
GPKS=Specific Gravity of PKS = 2.7
If the respective values (representing the varying water- cement ratio) of ‘x’ is substituted into the above equation then the weight of needed cement is gotten. Because 150mmx150mm cube was to be used, then the result gotten from here is converted from 1m3 to 0.0003375m3equivalents. When the value of the cement has been known, it can used to get the value (Weight) of other composite of the concrete for the particular water-cement ratio. This implies
X= weight of water in kg
Cement = weight of cement in kg
2 sand = weight of fine aggregates in kg
4 PKS = weight of coarse aggregate in kg.
The respective weights gotten from here are just for the production of one cube of concrete. A total number of 12 cubes are needed for the completion of the project. Then the cumulative weight needed will be multiplied by 12. An allowance of 2% was also added to the cumulative.
Since the test is from the 7th through 14th, 21st, 28th day after been cured in water and 3 cubes are needed to be crushed for each water- cement ratio, then on computation, the total number of cubes needed per ‘test-day’ per day is 5 (no of water-cement ratio)* 3= 15cubes of palm kernel shell concrete.
For the total number of cubes crushed for the experiment = 15 *4 = 60 cubes.
During casting, the use of tamping rod was employed to give the cubes maximum compaction. The standard laid down by BS8110 for the use of 150 x 150 x 150mm cubes was used, 3- layers and 35-blows for each layer with tamping rod.
On removal from the curing tank, the concrete cubes are drained of the water on their surfaces and left to dry before being weighted to determine its density (s).
Density = WEIGHT/0.003375 kg/m3
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ABSRACT - [ Total Page(s): 1 ]ABSTRACT IS COMING SOON ... Continue reading---
APPENDIX A - [ Total Page(s): 2 ] ... Continue reading---
CHAPTER ONE - [ Total Page(s): 3 ]CHAPTER ONE1.0 INTRODUCTION Concrete is a composite engineering material made from the mixtures of cement, water, fine aggregate (sand), coarse aggregates (such as crushed stones or rocks and granite) and a small amount of air in a specific proportion that hardens to a strong bony substance or become ossified. The cement always serves as a binder for the aggregate.The uniqueness quality of concrete makes it desirable as a building material, because it can be moulded into virtually ... Continue reading---
CHAPTER TWO - [ Total Page(s): 4 ]The water to cement ratio, or w/c ratio, largely determines the strength and durability of the concrete when it is cured properly. The w/c ratio refers to the ratio of the weights of water and cement used in the concrete mix. A w/c ratio of 0.4 means that for every 100 lbs of cement used in the concrete, 40 lbs of water is added. For ordinary concrete (sidewalks and driveways), a w/c ratio of 0.6 to 0.7 is considered normal. A lower w/c ratio of 0.4 is generally specified if a higher quality con ... Continue reading---
CHAPTER FOUR - [ Total Page(s): 6 ]CHAPTER FOUR4.0 DISCUSSION OF RESULTS4.1 Properties of Palm Kernel Shell {PKS}Results of the study from table 4.1 and figure 4.1 shows that the sieve analysis of PKS and the trend of the percentage cumulative weight retained increases as the sieve sizes decrease. The specific gravity of PKS was found to be 1.37 [Table 4.2] which [Okpala; 1990] classified as light weight aggregate.The water absorption capacity was found to be 10% [Table 4.3]. This value was considered in the design of m ... Continue reading---
CHAPTER FIVE - [ Total Page(s): 1 ]CHAPTER FIVE5.0 CONCLUSION AND RECOMMENDATION5.1 CONCLUSIONi. The result of the physical properties obtained show that PKS can be used as partial or complete aggregate substitution for lightweight structural concrete at 1:2:4 nominal mix.ii. The compression strength increases with advancement of age but decreases with increase in water cement ratios. That is, at w/c ratio of 0.3 the compressive strength is 6.5N/mm2 at 28 days while at w/c ratio of 0.5, it is 3.99N/mm2 at ... Continue reading---
REFRENCES - [ Total Page(s): 1 ]REFERENCENeville, A.M. (1996). “Properties of Concreteâ€. Longman Group Limited, London.Okafor, F.O. (1988). “Palm Kernel Shell as Aggregate for Concreteâ€. Cement Concrete Research Vol. 18, No 6, pp. 901-910.Okpala, D.C. (1990). “Palm Kernel Shell as a Lightweight Aggregate in concreteâ€. Building and Environment 25, pp. 291-296Olanipekun, E.A., Oluola, K.O., and Ata, O. (2006). “A comparative Study of Concrete Properties Using Coconut Shell and Palm Ker ... Continue reading---
