ABSTRACT
In this study, the compressive strengths and Modulus of elasticity of lightweight Concrete with oil palm shells as partial replacement of coarse aggregate was presented. The different types of mixing water were used, namely, clean water from Ahmadu Bello University Water Works, Salt water, obtained from Lagos Shore and Pond water obtained from Nagoye, Zaria. Also three mix ratios were adopted which include 1:2:4, 1:1.5:3 and 1:1:2 mix ratios. Five mixes were investigated; control, which contain granite coarse aggregate only; then four other mixes with 20%, 40%, 60% and 80% granite coarse aggregate replacement by oil palm Shell (OPS) aggregate. Fifteen samples where produced for each mix ratio, given a total of 135 concrete cube specimen for compressive strength tests and another 135 cylinder specimen for cylinder compressive strength tests and another 135 cylinder specimens for indirect tensile test for the determination of modulus of elasticity. In conclusion, after undertaking the laboratory practical?s on the OPS using 3 types of water for curing and varying the mix ratios to conform with class M15, M20 and M25, the effect of mix ratio and curing showed a tremendous difference but the use of OPS as a lightweight aggregate material was found to be adequate when compared with other materials being used as lightweight aggregate.