Geotechnical Investigation on The Behaviour of Fibre-Mixed Black Cotton Soil Under The Influence of Various Permeants for Barrier Application

Abstract

Engineered disposal systems are designed to isolate both domestic and industrial wastes from the natural environment by placing geotechnical barrier systems. Clay barriers function as low-permeability layers to effectively contain contaminants and prevent groundwater infiltration in landfills. This study investigates the use of naturally available black cotton (BC) soil as a barrier material due to its abundance and high montmorillonite content. However, its susceptibility to shrinkage limits its effectiveness. To address this, waste tire fibres—known to reduce shrinkage in clays—were added to BC soil at concentrations of 5%, 10%, and 15% (by dry weight). Considering engineering, economic, and environmental benefits, the fibre-mixed BC soil composite was evaluated for its suitability as a hydraulic barrier.