Evaluating the Effectiveness of Using Coconut Shell as Coarse Aggregate for Self-compacting Lightweight Concrete

This study investigates the structural properties of concrete when coconut shell is used as a partial replacement for coarse aggregate. The objective is to evaluate the effect of this replacement on workability, compressive strength, and flexural strength of concrete. Mix designs were prepared by replacing conventional coarse aggregate with coconut shell at varying percentages of 0%, 10%, 20%, and 30% by weight. Standard concrete tests were conducted, including slump tests for workability, compressive strength tests at 7, 14, and 28 days, and flexural strength tests at 28 days. The results revealed that slump values decreased with an increase in coconut shell content, indicating reduced workability. Compressive and flexural strengths also decreased with higher percentages of coconut shell; however, concrete with a 10% replacement showed acceptable strength for light structural applications. The study concludes that coconut shells  can be used effectively as a partial replacement for coarse aggregate in concrete for non-load-bearing and low-cost construction, contributing to sustainable waste management and reduction of construction costs.