Investigating properties of pervious concretes containing coconut shell flake and ash

Abstract

Pervious concrete or non-fine concrete is a simple form of lightweight concrete made by eliminating the use of fine aggregates. As a result of not using a fine aggregate in pervious concrete, then created a cavity filled with air and water can be passed. This cavity resulted in a reduced density of the concrete and the reduced amount of area that needs to be covered by a cement paste, thereby reducing the compressive strength. This study aimed to utilize waste material to increase the compressive strength of pervious concrete. The waste material was the coconut shell ash and coconut shell flake. The method was to strengthen the coarse aggregate concrete mixture. It was expected to increase the compressive strength along with the increase in permeability. Thus, in this study, the researchers will replace part of the coarse aggregate with coconut shell flake with percentage 0%, 2,5%, 5%, 7,5%, 10% and partially replace cement with coconut shell ash with percentage 0%, 2,5%, 5%, 7,5%. The results show that the combination of coconut shell flake and coconut shell ash does not increase the compressive strength of the concrete mixture. However, it increases the porosity, permeability, and as a result, the density is getting lower. Further study will be performed on porous concrete using coconut shell flake for lower load facilities, such as pedestrian or bicycle pathways.