Abstract: To study the deformation and failure process and hazard occurrence mechanism of a high cutting slope in Guangxi is presented in this paper. The rock strata, joint occurrence and deformation as well as the failure range and mode of the slope environment were determined through on-site geological survey, and then Phase2 software was used to establish a numerical analysis model that can reflect complex geological characteristics. The deformation and failure characteristics of the slope under the control of bedding and joints were evaluated. The results show that the dip joint is the main geological factor of slope deformation and instability. The tension cracks and rainfall infiltrations are the main causes of slope deformation and failure. The hazard process is excavation disturbance-joint tension-rainfall infiltration-rock mass weakening-joint tension displacement-deformation and failure. The construction disturbance caused the joint to be in a state of tension crack. Due to the rock anchor support, the deformation and failure did not occur on the slope surface. At this time, the factor of safety of the slope was 1.07; the rainfall infiltration leads to the weakening of the strength of strongly weathered siltstone, and the J1 joint further cracks and slips, and forms a shear slip zone along the interface between the layer and the joint and rock layer, and finally cuts out at the intersection of strong weathering and slope.

Key words: High Slope, Excavation Disturbance, Joint Slip, Deformation Damage, Numerical Simulation