ABSTRACT
The structure of the deposit is basically compacted with several exceptions. The properties of the deposit are spatially in homogeneous. A huge alluvial deposit is located on the left abutment of the Xiaowan arch dam, which has the maximum height difference of about 470 m and the total volume of 5.4 × 106 m3. The natural slope of deposit is stable, but the properties and mechanisms of the deposit, as well as the boundary conditions are extremely complicated. The deformation mechanism of the deposit slope was deeply carried out for the sake of safety and economy. For the slopes of the right abutment of the arch dam, different kinds of models for the stability analysis are established in the different portions and areas, according to the boundary conditions, the features of the rock texture and the slope shapes of excavating.
