Failure Evolution of Accumulated Landslide with Line-Like Interface between Sliding Mass and Bedrock under Combined Influence of Reservoir Water and Rainfall

To study the landslide response mechanism of accumulated landslide with line-like interface between sliding mass and bedrock under the coupling action of reservoir water and rainfall. Taking the Taping H1 landslide in Quchi County as an example, the characteristics of landslide movement and instability evolution mechanism are revealed through engineering geological survey and monitoring data analysis as well as combined with correlation theory and discrete element method. Taping H1 landslide has a stepped deformation mode, and the landslide deformation rate decreases with the rising of the elevation. Both reservoir water and rainfall are considered as governed external factors affecting landslide deformation, the seepage effect caused by the continuous drop of reservoir water resulting in obvious slope deformation at the front of the landslide, and during the fluctuation of reservoir water level, uninterrupted rainfall infiltration has a significant positive effect on the slope movement at the middle part of the landslide. Under the combined action of reservoir water and rainfall, the landslide instability will first occur at the surface rock mass at the toe, and then developed from the front of the landslide to the middle of the landslide, showing the landslide exhibited a multi-stage retrogression-type failure evolution. At present, the deformation at the front and middle parts of the Taping H1 landslide is continuous, and it is urgent to carry out landslide prevention and control projects to improve the landslide stability.