Effect of Water Content on Shear Strength of Black Cotton Soil

The bearing capacity of the soil is an important factor in the process of designing foundations on soil and it depends upon shear strength parameters C and Phi. The large part of the Maharashtra state is having black cotton soil which is vulnerable because of the fluctuation in water content in it. Due to the expansion and contraction property of black cotton soil, the shear strength varies with variation of water content. This research, it is focused to find the effect of moisture content on the shear strength of black cotton soil. The undisturbed samples of black cotton soil are explored from the site from desirable depth using the drilling machine. On explored samples, various field and laboratory tests are performed to find the strength parameters of the soil at different water content. This study gives different values of shear strength in black cotton soil with variation in moisture content. From the work, it has been seen that there is increase in the shear strength in the initial stage as water content an increased, later increase in the water content causes a decrease in the shear strength of black cotton soil. It indicates that, optimum water content should be maintained in the foundation soil to avoid excess settlement of foundations in soil.