Evaluation of Swelling Behaviour and Soil Water Characteristic Curve of Bagasse Fibre and Lime Stabilised Expansive Soil

This paper presents an experimental investigation on the enhancement of swelling behaviour and soil water characteristic curve (SWCC) of bagasse fibre and lime stabilised expansive soil. Lime stabilisation is commonly used to improve the engineering properties of expansive soil. Bagasse fibre, an industrial waste by-product left after crushing of sugarcane for juice extraction, was used in this study as reinforcing component in combination of lime for expansive soil stabilisation. The expansive soil used in this investigation was collected from Queensland, Australia. In order to investigate the influences of combination of bagasse fibres and lime on the engineering behaviour of unsaturated expansive soil, a variety of stabilised soil samples were prepared by changing proportions of randomly distributed bagasse fibres combined with different lime contents. An array of experimental tests was performed including free swell potential, swelling pressure, and one-dimensional consolidation tests. Soil suction tests were conducted using the contact filter paper technique on natural and stabilised expansive soil samples. The results revealed that lime-bagasse fibre treatment of expansive clay has a significant effect on swelling behaviour and SWCC response of treated soils. Combination of hydrated lime and bagasse fibre resulted in more improvement on swelling behaviour of soil samples when compared to that treated with lime only. The air entry value of stabilised expansive soil increased with an increase in the stabiliser content.