Abstract:

Based on detailed study engineering geological conditions of slope at left abutment of Wudongde hydropower station, using a combination research means and methods of engineering geological analysis evaluation，limit equilibrium method and numerical calculation, the global and local stability of artificial slope at left abutment of Wudongde hydropower station is studied. The results show that the slope is stable as a whole from 3D distinct element simulation. The safety coefficient is 1.4-1.6 of the artificial slope is among 1.4 and 1.6 and its deformation is dominated by a small amount of rebound deformation and deformation characteristics without highlighting. Based on analyzing boundary condition of block formed after excavation, block instability mode was proposed. Starting with block stability influencing factors：geometric features, property and unloading and relaxation feature of structural plane, a block stability engineering geological evaluation standards is established and is applied in this project.  A 3D rigid limit equilibrium method is used to analyze the stability of the potential failure block in abutment slope. The results show that most block was basically stable. Then some reinforcement measures are put forward for the high slopes based on global and local stability of slopes.The research results provide an important basis for design and construction.

Key words: high rock slope, engineering geology, 3D distinct element method, instability mode analysis, 3D limit equilibrium analysis method