Abstract: With the continuous development of urban areas, there are more and more rock slope excavation and support problems, and the research on the stability of the slope excavation process becomes more and more important. This study intends to establish a Midas-GTS-NX three-dimensional numerical analysis model for a rock slope of a subway station in the mountainous area and analyze the stress distribution within the slope and the settlement of the road surface at the crest of the slope during the different stages of rock slope excavation. The study results show that the stability factor of safety of the slope is 1.10 in the initial state of the slope, and it is in a marginal stable state. The excavation of the slope causes a large stress concentration phenomenon at the bottom of the excavation area, but the shear stress value less than the shear strength value of the sandstone rock structure, the foundation excavation project will not have shear failure; due to the reinforcement of the soil at the top of the slope, the displacement and deformation value of the crest of the slope during the excavation process is small, which will affect the road surface. The rock slope structure will not be damaged; for the horizontal displacement value, tangential displacement value and settlement value of the upper retaining wall of the slope at different slope excavation stages, the simulation results are all less than the on-site monitored values, but the trend of the simulation results is the same as the on-site monitored data. The same, and the displacement values of the retaining wall during the slope excavation are all within the stable range. These study results can provide references for the similar type of projects.

Key words: Rock Slope, Numerical Simulation, Step-by-Step Excavation, Stress Distribution, Displacement