Properties of Fly Ash Based Coconut Fiber Composite

Abstract

The present paper reports the results of a study undertaken in enhancing properties of fly ash concrete composites-FMCC with locally available natural fiber. In this context a composite with fly ash, concrete and treated coconut fibers-available in plenty in rural areas of India-can be a good proposition and with this background, experimental investigation to study the effects of replacement of cement (by weight) with different percentages of fly ash and the effects of addition of processed natural coconut fiber on flexural strength, compressive strength, splitting tensile strength and modulus of elasticity was taken up. A control mixture of proportions 1:1:49:2.79 with w/c of 0.45 was designed for the normally popular M20 concrete. Cement was replaced with five percentages (10, 15, 20, 25 and 30%) of Class C fly ash. Four percentages of coconut fibers (0.15, 0.30, 0.45 and 0.60%) having 40 mm length were used. Test results show that the replacement of 43 grade ordinary Portland cement with fly ash showed an increase in compressive strength, splitting tensile strength, flexural strength and modulus of elasticity for the chosen mix proportion. Addition of coconut fibers resulting in fly ash mixed concrete composite -FMCC- did enhance the mechanical properties of FMCC and at the same time increased the energy levels reflected by increased failure strain, making the material suitable for seismic sustenance.