10. Performance of Highway Subgrade Soil Stabilized with Lime and Slag

As soil is the major component of highway transport system, it is essential to check the performance of soil for its strength and plasticity before design and develop any transport related infrastructure. Soft or weak soil faces many difficulties leading to collapse of structures. Soil stabilization is a technique used to maintain or improves the quality and stability of weak soils to achieve the required engineering goals. For enhanced effect of soil stabilization, industrial wastes have been proved promising as admixture. However, the exact content of particular admixture for clayey soil plays an important role in stabilizing and strengthening soil. In this research work, the authors are presenting the experimental results in evaluating the engineering performance of expansive subgrade soil stabilized with lime and Ground Granulated Blast-furnace iron Slag (GGBS). The work methodology includes the stabilization of the expansive soils with various percentages of lime and slag to determine the soil properties and to find their optimum content of stabilization. Extensive laboratory testing has been conducted to determine the soil properties such as consistency, compaction, swelling characteristics, unconfined compressive strength and bearing capacity to depict strength and deformation behavior of the subgrade material. The soil properties were found as increasing continuously up to 11% by the treatment with GGBS and with the addition of lime, the values were observed continuously increasing up to 7% and then decreasing.