Abstract：In order to study the effects of non-coplanar overlapping flaw inclination on the axial stress，elastic strain energy and local stress field of rock-like specimens under uniaxial compression，numerical simulation adopting particle flow numerical analysis software PFC2D was carried out based on the actual parameters of existing rock-like samples. The results show that the compressive strength of the rock sample increases with increasing the dip angle of the flaws. When the dip angle of the flaw is small，the sample has obvious plastic deformation during uniaxial compression and the energy release rate is large in the strain softening stage. In the case of a large dip angle of the flaw，the sample shows obvious elastic brittleness and large energy storage capacity. Analysis of the local stress field of the flaws indicates that the minimum principal stress field obviously changes with the axial strain. The large stress drop is related to the accelerating propagation of the cracks. The minimum principal stress filed can be classified into three different types according to the variation of the stress field. In the early stage of loading，the minimum principal stress of the upper and lower sides of the flaws is tension stress. With increasing the dip angle of the flaws，the stress concentration decreases，the tension zone is transferred to the tip of the flaws and the area is gradually reduced. The tensile stress gradually disappears after the flaw is cracked. Although the stress concentration near the tip of the flaw is high in the early stage of loading，the two-dimensional compressive stress state makes the crack initiation of the region relatively difficult.
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2019, Vol. 38 
