Deformation mechanism and reinforcement design for the flexural toppled slope of Miaowei HPP.

Toppling is a typical failure mode of a rock slope. The deformation mechanism and sliding mode of a toppled slope are considerably different from those of conventional slopes. The analysis methods and reinforcement strategies for conventional slopes have some limitations in toppled slopes, especially flexural toppled slopes. In this paper, the right bank slope of the Miaowei hydropower plant was taken as a case study. Based on the qualitative understanding, the method of discrete element analysis is used to “reproduce” the deformation and failure of the slope and analyze the mechanism of deformation and failure. Based on the knowledge gained from the discrete element analysis, closed-loop feedback analysis was carried out to design the reinforcement measures. The analysis confirmed that the excavation in the lower part of the slope and heavy rainfall dominate the formation of sliding failure along the toppling-induced fracture zone. With this understanding, strong anchorage on the middle and lower parts of the slope was planned. Meanwhile, more drainage measures were also designed. The slope was relatively stable during excavation, and the effectiveness of the analysis method and design measures was confirmed. The research results can be used to guide the treatment of flexural toppled slopes. [ABSTRACT FROM AUTHOR]