Numerical Analysis of Crack Propagation Evolution of Specimens with Different Dip Angles of Cross Fractures

In order to study the failure modes and crack propagation laws of uniaxial compression specimens with different dip angles, a mathematical model was established using the discrete element program PFC2D. The crack initiation, expansion and extension of the simulated specimens were analyzed by tuning the horizontal angle under various working conditions. The effects of tensile cracks and shear cracks on crack propagation were comprehensively analyzed using the failure mode combined with the displacement field and the stress–strain curve. The results showed that the failure mode was first shear failure, then composite failure and finally tensile failure as the horizontal angle increased. Meanwhile, the stress decreased, increased and decreased again as the horizontal angle increased. The study of compressive failure of cross-cracked specimens at different dip angles serves as an important guide for roadway support and underground space excavation.