Discrete Element Simulations of Cyclic Biaxial Shear of a Granular Material with Oval Particles

Abstract

Discrete element method (DEM) simulations are used for measuring the macroscale and microscale changes in stress and fabric for the cyclic loading of a two-dimensional granular assembly. The stress–strain–dilatancy tendencies are similar to those of sands. After repeated loading cycles, the fabric follows a steady-state circuit of evolution within each cycle, but reversals in the loading direction are always accompanied by abrupt changes in the fabric. A consistent and strong inverse relationship is found, however, between the average coordination number and an effective void ratio, defined by excluding particles that do not participate in supporting the applied stress. A strong and consistent correlation is also found between the deviator stress ratio and a trong fabric ratio throughout the cyclic loading.