Description:
In order to research the crack initiation and propagation behavior in rock mass under coupled static and dynamic loads, the crack initiation angle and expansion angle formulas are set up by use of the fracture mechanics theory, then numerical simulation of crack propagation are conducted using software RFPA. The results show that: the crack always extend toward the dynamic stress direction; the bigger of the crack dip, the smaller of the crack initiation angle and the more difficulty of the crack initiation and propagation, meanwhile the less influence to the damage of rock. What’s more, when the crack dip is small, theoretical value and numerical simulation value of initiation angle will be have good uniformity.