Particle-scale simulations of the compression and shearing of kaolin clay

Abstract

This paper presents a new model for particle-scale simulations of clay. Using the discrete element method (DEM), featuring realistically-shaped platelets with separate interactions between the various platelet surfaces, simulations of isotropic normal compression and triaxial shearing are performed. A normal compression line is established, and for the first time so is a critical state line, which is parallel to the normal compression line in e-log p space. The critical state line is obtained from conventional, constant mean stress, and constant volume tests on normally consolidated and overconsolidated samples. The critical state line appears linear in q-p space and the first insights into a state boundary surface for the clay are established. This new model appears capable of capturing the key features of macroscopic clay behaviour.