Modeling the deformation behavior of sandstone using a bonded-particle model

摘要

According to the previous researches, it was found that the key microscopic parameters influencing strength and deformation of sandstone are porosity and grain area ratio (GAR). In this study, numerical analyses based on the bonded particle modelwere conducted to systematically explore the relations between the mechanical behaviors and the abovementioned factors. The model is firstly verified by simulating the uniaxial compressive test. Furthermore, the elasto-plastic deformation of sandstone with different porosity and GAR is explored by means of triaxial tests. Analysis results indicate the following characteristics: (1) The greater GAR and porosity lead to the less cohesion, and the higher porosity leads to the lower friction angle; (2) The elastic shear modulus increases with decreasing porosity and increasing GAR; and (3) The variations of plastic angle and plastic strain trajectory under shearing are similar to actual behaviors of sandstone, and the higher porosity leads to the more plastic strain.