Estimation of Tri-axial Behaviour of Pilani Soil Using the Results of Direct Shear Test as a Function of Pore Water Content

Abstract

Shear strength of soils have two distinct components, cohesive component and frictional component. Literature study has been made to study the origin of these components of shear strength based on interparticle interactions. Effect of pore water content onto its shear strength components have been discussed. Standard laboratory experiments are available to determine shear strength components of soil. Direct shear testing and triaxial testing are two such techniques. Triaxial testing better simulates field conditions. However, direct shear testing is more simple to perform. Based on literature study, details of direct shear testing and of triaxial testing has been provided in the study. Using the results of direct shear testing, triaxial behavior of local soil has been estimated as a function of pore water content. Locally available soils of sands and silty clayey type have been collected. Specific size particles from both soil types were taken. For this composition and at 5 different water content, shear strength parameters were determined by conducting direct shear testing. Using the results of direct shear testing, tri-axial testing behavior of soil (as a function of pore water content) for a particular confining stress of 0.03MPa has been determined. Practical significance of the results has also been discussed.