Stability analysis of earthquake-induced rock slope based on back analysis of shear strength parameters of rock mass

High-steep rock slopes are much more likely to collapse and form weir body due to earthquake. Converting the weir body to hydraulic engineering is a good way to deal with natural disasters. However, it is difficult to evaluate the stability of earthquake-induced rock slope due to the lack of shear strength parameters of rock mass. Based on three-dimension nonlinear finite elements, deformation reinforcement theory was adopted, in which plastic complementary is used to measure the global stability of slope, and unbalanced forces is utilized to identify the damage region. The shear strength parameters has been determined through back analysis based on stability and failure status before and after earthquake and monitoring data after earthquake. Then the stability evaluation under static conditions, dynamic conditions and rainfall conditions has been carried out respectively. The results show that failure mode of the slope under seismic load is consistent with the actual situation when the lowest material parameters are used. The major failure mode of the slope is sliding along the fault F5, and local collapse of the hanging body at the top of the slope under dynamic or rainfall load. The local stability can be improved effectively by excavating and taking bolt anchorages on the top of the slope.