Utilisation of Waste Shea Nutshell Fine-Grained Particles to Enhance Strength and Durability Behaviour of Concrete

Abstract

Shea nutshells possess properties that stabilise soil enough to resist water penetration. It is a waste material and incorporating it as an additive material in concrete will be a means by which it can be recycled. With this projection, the study incorporated shea nutshell particles (SSP) as fine aggregates in concrete. The aim was to determine their influence on strength and durability properties. Fine aggregates were partially replaced with 0%, 10%, 20%, 30%, and 40% SSP based on the weight of the aggregate, and labelled as A0, S10, S20, S30 and S40 respectively. Concrete cubes of size 150 mm and cylinders of diameter 150 mm and height of 300 mm were prepared and cured for 7, 14, 28, and 90 days. The concrete was tested for density, compressive strength, split tensile strength, water absorption, and sulphate attack. The inclusion of the SSP did not improve the compressive and split tensile strengths. However, water absorption and sulphate attack decreased with further addition. Though, strength properties did not appreciate, values at 10%, 20% and 30% additions in 28 and 90 days satisfied the 28 days minimum requirement of 25 N/mm2. Hence, the study recommends the use of SSP in concrete production up to 30%.