Study on instability mechanism of anisotropic structural planes of coal and rock under unloading

Currently, the research on the slip instability of rock mass structural planes has not considered the unloading effect during heading. There is relatively little research on the anisotropic structural planes of coal and rock. In order to explore the conditions and influencing factors that trigger the slip of anisotropic structural planes of coal and rock, a mechanical model of anisotropic structural planes is established. A criterion for unlocking slip of anisotropic structural planes under unloading is theoretically derived. A smooth structural plane numerical model is established using universal distinct element code (UDEC) to verify the accuracy of theoretical analysis of the triggering conditions for unlocking the slip of anisotropic structural planes. The influencing factors of unlocking slip of anisotropic structural planes are analyzed. The research results indicate that unlocking slip of anisotropic structural planes of coal and rock is related to the inclination angle of structural planes, internal f