Deformation and stability analyses of a near-dam rocky slope and its potential landslide-generated wave threats

Occurrence of a reservoir landslide and its potential secondary hazards near a dam can result in significant losses and casualties, such as those that resulted from the Vajont landslide. In this study, a cataclinal rock slope in the Maoergai reservoir was taken as a case to study the characteristics of the gravitational deformation process and to analyze the potential threat. The stability of rock slope is analyzed by the limit equilibrium method, and the potential landslide movement and subsequent waves are also simulated. Results indicate that lithology, geological structure, reservoir water level changes and artificial activities all play an important role for the large deformation of rock slope deformation, which is characterized by a combination of bending-toppling and principally shear-slip. Pre-calculations of potential threats indicated that the impact of a landslide wave would be greater at dead water levels than at the normal water level and could result in blockage of the inlet to the water diversion structure on the opposite right bank. These findings provide implication for the control of reservoir rock slopes: (i) serious attention should be paid to the influence of water on rock strength in early and (ii) infiltration must be prevented during water level rise. Thematic collection: This article is part of the Role of water in destabilizing slopes collection available at: https://www.lyellcollection.org/cc/Role-of-water-in-destabilizing-slopes