Coconut Shell as a Substitute for Coarse Aggregate in Concrete

The high demand for concrete in the construction using normal weight aggregates such as gravel and granite drastically reduces the natural stone deposits and this has damaged the environment thereby causing ecological imbalance. There is a need to explore and to find out suitable replacement material to substitute the natural stone. In India, commercial use of non-conventional aggregates in concrete construction is not practiced yet. India is the third largest producer of coconut products in the world. Coconut trees are widely cultivated in the southern states of India, especially Kerala. Coconut shells as a substitute for coarse aggregates in concrete is gaining importance especially in this region in terms of possible reduction of waste products in the environment and finding a sustainable alternative for non-renewable natural stone aggregates. The properties of concrete using crushed coconut shell as coarse aggregate were investigated in an experimental study. Coarse aggregate was replaced by crushed coconut shells in three different percentages namely 25%, 50% and 100%. Workability, compressive strength, flexural strength and splitting tensile strength of the above said mixes were compared with normal concrete properties. The results from the study is expected promote the use of coconut shell as a substitute for conventional coarse aggregates.