Stability Studies of Buoyancy Weight Loss Landslides under Different Speed of Reservoir Water Level Fluctuation

Landslide is one of the most serious geological hazards in the Three Gorges reservoir regions since the reservoir was in operation in 2003. Reservoir water level changing has become one of major factors that affect the stability of landslide. In order to study the impact of the wading landslide's stability induced by water level fluctuation,it analysised the buoyancy weight loss landslides based on the classification of significant wading landslide. Taking Shuiwenzhan Landslide for example,Geo-Studio finite element software was adopted in numerical simulation calculation on seepage field and stability under different conditions. The results show the stability coefficient decreases with the reservoir water level increasing and rise with the water level lowering; the stopping slide sect is submerged gradually,the underwater rock mass gravity reduces and the resisting force of stopping slide sect decreases with the reservoir water level increasing resulting in lower landslide stability; effective stresses of the landslide increase with the reservoir water level lowering and the gravity decreased,so as to make the landslide stability increase. It will provide scientific basis for the forecast or treatment of landslide in Three Gorges reservoir.