Abstract: The influences of crack inclination angle, rock bridge’s inclination angle and biaxial load on rock crack propagation mode were studied by using Rock Failure Process Analysis(RFPA-dynamic) on rock samples with pre-existing cracks. The results show that 1) under uniaxial dynamic load, crack inclination angle and rock bridge's inclination angle have little effect on crack propagation , and the crack expands in the direction perpendicular to load; 2) the release of accumulated energy of acoustic emission can be divided into four stages under axial dynamic load; 3) under biaxial load, along with the decrease of load ratio, the bending radian of crack increase and the crack is gradually perpendicular to the horizontal load; 4) when the inclination angle of rock bridge is constant with the increase of crack inclination angle, crack tends to the vertical direction under biaxial dynamic load; 5) under uniaxial static load, crack inclination angle and rock bridge’s inclination angle have significant effect on crack propagation mode but have little effect under uniaxial dynamic load.

Key words: rock mechanics, inhomogeneous medium, dynamic load, crack propagation, numerical simulation