Abstract: The influence of reservoir water level on rock strength in the water level variation zone was researched through immerse-dry test on sandstone collected from typical bank slope in Three Gorges Reservoir area. The degradation of rock mass parameters in the presence of different water levels was deduced by using the test results and RMR method. Furthermore, the impact of rock degradation in the variation zone on the stability of a typical landslide in the Three Gorges Reservoir Area was analyzed through numerical simulation. Results reveal that the increase and drawdown of water level has obvious deterioration effect on rock mass, and shortens the time of bank slope failure. The reservoir bank collapse is directly related with the landslide stability and may cause the reliving of landslide. This research is a reference for analyzing the long-term stability of landslide in the reservoir area.

Key words: bank slope of reservoir, immerse-dry test, variation zone of reservoir water level, landslide relive, RMR method