Overtopping Risk Analysis of Earth Dams considering Effects of Failure Duration of Release Structures
Table 2
Ranks of slope stability and linguistic descriptions of the likelihood of a seismic landslide.
Slope
Brief description of slope
Stability rank
Likelihood of seismic landslide
Spillway slope
The dip angle of the slope is 35°∼45°. The slope is mainly composed of gravelly soils and weathered unloading rocks.
3
Fairly likely
Inlet slope of flood discharging tunnel
The dip angle of the slope is 30°∼40°. The slope is mainly composed of colluvial gravelly soils.
2
Even
Outlet slope of flood discharging tunnel
The average dip angle of the slope is 55°. The unloading effect of the superficial rocks is quite significant, which results in the tensile deformation of the rocks. The aperture of rock fracture is 1∼4 cm wide.
5
Highly likely
Inlet slope of power station diversion tunnel
The slope is rather steep and consists of colluvial gravelly soils.
3
Fairly likely
Outlet slope of power station diversion tunnel
The slope is steep and mainly consists of weakly weathered and unloading rocks. There is a significantly unloading rock mass at an elevation of 875 m, part of which had collapsed and buried the tailwater outlet.
6
Very likely
Inlet slope of the emptying tunnel
The dip angle of the slope is 35°∼50°. The slope is mainly composed of colluvial gravelly soils. The slope had largely deformed.
4
Likely
Outlet slope of the emptying tunnel
The slope is gentle and mainly consists of weakly weathered rocks.
