Constitutive relations for cohesionless frictional granular materials

Based on the micro-mechanical model recently developed by Namat-Nasser S. (J. Mech. Phys. Solids 48 (2000) 1541), a three-dimensional continuum mechanics model is presented for the deformation of granular materials which carry the applied load through frictional contacts. The model incorporates the anisotropy (or fabric) which develops as a frictional granular mass is deformed in shear, and includes the coupling between shearing and volumetric straining (or dilatancy). The model parameters are estimated. based on the results of a series of cyclic shearing experiments on large hollow cylindrical samples of silica sand. Then, the model is used to predict other experimental results, arriving at good correlation. (C) 2002 Elsevier Science Ltd. All rights reserved.