In order to study the crack propagation characteristics of jointed rock mass under static and dynamic loads,the failure modes of jointed rock mass under dynamic and static loads were studied by laboratory tests and particle discrete element program PFC2 D5.0.The influence of joint inclination angle on failure mode under different loads was analyzed.The results show that the critical angle of the transition between the wing crack and the secondary crack is equal to 45.When the dip angle is less than 45,the new crack is mainly wing crack,crack initiation and rock mass damage are mainly controlle...