The Performance of the Low Cost Masonry Cement Blocks as a Partial Substitution of Coconut Shell Ash

Abstract

Aim of the research was to investigate the effect of Coconut Shell Ash (CSA) with cement as a partial substitution in the production of alternative cement blocks to subsist conventional ones. Utilization of this natural agro waste material helps to prevent the environmental pollution, reduces the construction cost as well as contributes to sustainable construction. Therefore, 90 blocks of 450 mm × 150 mm × 225 mm masonry cement blocks of mixing value 1:6 were cast, cured and tested after 7, 21 and 28 days. CSA was substituted at 0 to 50 wt.% at 5% intervals. The materials were mixed well with the addition of sufficient water. The maximum compressive strength and flexural strength of 300 kg/cm2 and 12.52 kg/cm2 were recorded at 5% supersession at the 28th day, respectively, which is found congruous and recommended for building construction having procured a 28th day compressive strength of more than 280 kg/cm2 as required by the Sri Lankan Standards. The compressive and flexural strengths of the cement / CSA blocks generally decrease as the percentage of CSA content increases. However the dry density, water absorption, compressive strength and flexural strength results conclude that the 10% CSA addition is the optimal value for the production of environmental friendly low cost alternative cement blocks.