Abstract:To explore the laws of rock seepage and shear failure, sandstone was taken as an example, RFPA2D software was used to carry out numerical simulation. The results show that the sandstone is divided into four stages in the process of seepage and shear failure: stable deformation, meta-stable deformation, instability precursor, and instability failure; along with the loading process, the stress in the center of the model deviates and rises, followed by stress concentration. However, a small amount of microcracks are generated, and the tensile microcracks appear earlier than the shearing microcracks. After the two merge and penetrate, a macroscopic fracture surface is formed; the acoustic emission activity runs through the entire seepage shear failure process, which appears before the peak shear stress. Acoustic emission characteristic parameter index is low, afterwards, the acoustic emission characteristic parameter index increases sharply. The comparison of the crack propagation diagram and the acoustic emission diagram illustrates the crack propagation law in the process of sandstone seepage and shear failure. Studying the failure process of rock under the coupling action of shear load and rainfall seepage has important engineering application and practical significance. The use of RFPA2D software simulation can provide new ideas for the study of the stability of rock slopes affected by rainfall.