Strength and Durability Characteristic of Lime Stabilized Black Cotton Soil

Expansive soil which is found in several parts of India possesses high swelling and shrinkage properties. The volume change and uplift pressure generated in these soil deposits cause severe damage to the lightweight structures and pavements. In order to mitigate the problems associated with expansive soils, it is necessary to stabilize this soil. Among all the stabilization techniques, lime treatment is one of the best suitable methods for expansive soils. In the present study, lime stabilization technique is used to improve the engineering properties of black cotton soil including the resilient modulus value, which is important for mechanistic flexible pavement design. Optimum amount of lime required for stabilization was determined using Atterberg’s limits. Considerable increment was observed in unconfined compressive strength values and California bearing ratio values of black cotton soil stabilized with 6% lime. Repeated load triaxial tests under different confining pressures and deviatoric stress levels were conducted on the treated samples in order to determine the resilient modulus. The effect of curing period and moisture content on the resilient modulus was investigated. In order to study the durability of lime stabilized clayey subgrade soil, the effect of wetting and drying cycles on the engineering properties of the treated material was examined. The results show that the strength and stiffness characteristics of lime treated clay have considerably reduced after five wetting and drying cycles.