ELASTOPLASTIC DEFORMATION FOR PARTICULATES WITH FRICTIONAL CONTACTS

Perceiving granular material as a collection of particles, a constitutive law for granular material is derived based on a micromechanics approach, taking into account the mechanisms of sliding and separation of particles under large deformation. One of the major obstacles to account for the particle sliding associated with large deformation is the nonuniform strain field. In this paper, we tackle this problem by using a self-consistent method to account for thc heterogeneous field of strain. The micromechanical approach is described to illustrate the three levels of granular material, namely, representative unit, microelement and interparticle contact. The overall stress-strain relationship is expressed in explicit terms of interparticle contact properties. The present theory is evaluated by comparing the predicted stress-strain behavior of a granular packing with that obtained from computer simulation. The unique features of the present theory are discussed to show its usefulness in comprehensive modeling of complex behavior for granular material.