Abstract:In this paper,by systematic numerical modeling by the distinct element method with UDEC code, the effect of physical and mechanical properties of rocks including internal friction angle,Young’s modulus,Poisson’s ratio,and cohesion on stress field in the vicinity of fractures are analyzed. It is shown that the variation of all of these properties may cause the change of stress fields in the vicinity of a fault. Meanwhile,the effect of physical and mechanical properties of rocks co-exists with that caused by the change of mechanical properties of fractures and boundary conditions. In the modeling,both the single fracture model and compound fracture model are studied respectively. It is found that the Young’s modulus of rocks has a strong influence on the variation of rock stresses in the case of compound fracture model.