Macroscopic and microscopic shear failure characteristics of anchored penetrating jointed rock mass

In order to study the shear failure characteristics of anchored jointed rock mass, according to the indoor test and particle flow software PFC^2D, the shear behavior and internal meso-crack evolution of the anchored rock mass under different normal stresses and different anchoring angles are analyzed. The researches show that: (1) With the increasing of the anchoring angle, the shear strength of the anchored rock mass increases first and then decreases, and when the anchoring angle is 60°, the shear strength is the largest and the anchoring effect is the best. With the higher the normal stress, the higher the shear strength of the anchored jointed rock mass, the better the shear resistance. (2) As the shear displacement increasing, a small number of cracks generated in the early stage near the anchor and joints, through continuous outward expansion, eventually gather a large number of cracks at the joint between the anchor and the joint, where in the crack, the tensile crack is dominant. (3) The anchoring angle and normal stress have a significant influence on crack propagation. With the increasing of normal stress, the number of cracks also shows an increasing trend, and the rock mass damage is more serious. With the change of the anchoring angle, the number of cracks formed when the anchored rock mass is destroyed firstly decreases and then increases, and when the anchoring angle is 60°, the cracks are the least.