ABSTRACT
The soil sample was blended with varying proportions of sand alone, and a combination of sand and Lime Kiln Dust (LKD). The laboratory results were analyzed based on the effect of the additives on the engineering properties of the soil sample. From the test results on neat soil sample, it was observed that black cotton soil had a high plasticity index, high swelling potential, and low bearing strength. The addition of sand-LKD to black cotton soil sample exhibited a significant improvement in strength, and reduction in the plasticity index and swelling potential. The application of 30% sand and 3% LKD increased the CBR value of the neat sample from 5% to 18%, reduced the PI value of the native soil from 49% to 10.2%. This combination satisfied all the Ministry of Works and Transport subgrade specification requirements and was considered as the optimum stabilizer content for black cotton subgrade soils.
