Deformation Behavior of Sand Under Shear—Particulate Approach

Abstract

The deformation behavior of sand under shear loading is studied, based on the concept of particulate mechanics with consideration of the slip and nonslip contacts between the sand grains on a macroscopic shear plane. The “fabric factor” of a sand, which depends on the distribution of the contact angles between sand grains, is introduced to correlate the state of stress and the fabric of sand under shear loading. The relationship between the shear‐stress ratio and the fabric factor, and the relationship between the fabric factor and the dilatancy rate of a sand are developed. A stress‐dilatancy relation for sand under shear loading is then derived. The proposed model can better describe the deformation behavior of sand under cyclic loading. The results of slow, cyclic, drained, direct shear tests and drained, cyclic, triaxial shear tests agree reasonably well with the proposed stress‐dilatancy relation. The experiments also confirm the concept of fabric factor and existence of nonslip contacts between sand grains.