Rock failure modes and acoustic emission characteristics under different fissure angles

To accurately identify the acoustic emission characteristics and failure patterns of rocks with different fracture dip angles, a uniaxial compression model for heterogeneous rocks with varying fracture angles was developed using the discrete element method (DEM) simulation, combined with laboratory uniaxial compression experiments. Results show that smaller differences between the fissure inclination angle and the loading direction lead to less deterioration effect of the structural surface of fissure on the rock specimen. The damage rupture degree is relatively intense at the tip of the fissure structure surface and the center of the macro crack. The micro and macroscopic damage inside the rock specimen is mainly tensile damage. When the inclination angle of the fissure is small, the extension direction of the shear crack at the tip of the structural face of the fissure is approximately 90° from the fissure angles and continues to develop to the distal end until it runs through the whole rock specimen. When the inclination angle of the fissure is larger, the extension direction of the shear crack at the tip of the fissurestructure is approximately parallel to the fissure angles.