Mechanical Study on the Effect of Granular Friction in a Granular System under Biaxial Compression

The influence of granular friction on the mechanical behaviors of a granular system is a typical research realm that is still not yet fully understood because of the complexities and the discreteness of the granular system. In this study, a two-dimensional model of a granular system with biaxial compression is established by using the discrete element method (DEM). Using this DEM model, we investigate the macroscopic mechanical behaviors, the microscopic mechanical responses and the force chain distributions of a granular system influenced by granular friction. Simulation results show that the granular friction has a prominent influence on the stress-strain response, dilatancy behaviors, and peak strength of the granular system. The microscopic mechanical behaviors of the coordination number, the sliding fraction, and the mean mobilized friction coefficient of the granular system are also shown to be markedly influenced by the granular friction. The force chains in the granular system form an inhomogeneous distribution, and their intensities increase with increasing granular friction.