Effect of fiber length on the consolidation parameters of coir fiber-reinforced soft clay

Abstract

Coir fibers are natural fibers with high tensile strength and pressure resistance, making them an alternative soil reinforcement material. However, the effect of fiber length on improving soil consolidation properties has yet to be largely explored. Therefore, this study investigated the effect of the length and content of coir fibers on soft soil mechanical behavior through a series of one-dimensional consolidation tests. Fibers of >10 mm to 30 mm and >30 mm to 50 mm lengths were mixed randomly into the soil with varying content, ranging from 0.00% to 1.25% of the total weight of the mixture. The relationship between the effective stress and the void ratio was explored, unveiling that the void ratio of soil specimens reinforced with coir fibers decreased more gradually than those unreinforced. An increase in the fiber content reduced the compression index (Cc) value and enhanced the coefficient of consolidation (Cv) value, with longer fibers producing more significant values due to more excellent interactions between fibers. Fibers of >30 mm-50 mm yielded optimum Cc and Cv values at the fiber contents of 0.50% to 0.75%.