Quality improvement of coconut shell aggregate in lightweight concrete

Abstract

This study focused on the enhancement of quality of coconut shell aggregate using different pre-treatment methods and their effects in lightweight concrete. The degradability of coconut shell aggregate was tested by exposing the aggregate to severe alkaline, acidic and sulphate solutions. The quality of this aggregate was improved by providing pre-treatment with different chemicals. The properties such as water absorption, aggregate impact value and aggregate crushing value were tested. It was observed that coconut shell aggregate treated with 20% Poly Vinyl Alcohol (PVA) improved the performance of the aggregate. For instance, the water absorption of PVA treated aggregate was reduced to 42.27%when compared to that of non-treated aggregate. Furthermore, the aggregate treated with 20% PVA showed a marginal (only 5%) improvement in the strength of coconut shell aggregate concrete. Therefore, it may be concluded that coconut shell aggregate may not degrade when it is bound with concrete.