Feasibility of improving impact resistance and strength properties of sustainable concrete composites by adding kenaf fibres

Abstract

Waste materials utilization is one of the central concerns of waste management approaches in recent years. The developments in cement and concrete technology towards the production of sustainable concrete by using waste materials and cellulosic fibre is gradually attaining acceptance because of its technological, economic and ecological advantages. This research presents the potential use of a natural fibre known as Kenaf fibre and Rice Husk Ash (RHA) from agricultural waste towards achieving a bio fibrous concrete with enhanced impact resistance and strength properties. Four mixes with varying percentage of RHA from 0% to 15% at 5% step intervals without fibre was used as a basis for comparison against another four mixes made with 50 mm length fibre of 0.5% volume fraction. The drop weight impact test method was adopted in determination of the impact resistance strength and energy absorption of the RHA based kenaf fibrous concrete. At later ages, the compressive strength of the fibrous concrete mixtures containing 15% RHA significantly increased, and the obtained values were higher than the mix with Portland Cement (PC) alone. The positive interaction between Kenaf fibres and RHA leads to high tensile strength, flexural strengths and impact resistance, thereby increasing the concrete energy absorption capacity. It is concluded that concrete containing 0.5% volume fraction of 50 mm length Kenaf fibre and 15% RHA can be used as building materials in the construction of sustainable concrete