三峡库区某滑坡流固耦合分析及失稳预测

Interaction of Coupling Seepage and Stress of a Landslide in the Three Gorges Reservoir and Instability Prediction

三峡库区建成后,在库水的周期性涨落作用下,一些滑坡的地质条件已显著改变。有些滑坡已近失稳边缘,若此时遭遇库水下降影响及强降雨的作用,滑坡极有可能失稳。介绍利用大型通用有限元软件ABAQUS对三峡库区某滑坡在库水下降及降雨作用下进行流固耦合计算,并分析其应力场和位移场的变化结果,提取水平位移数据作为滑坡变形预测依据,得到库水位由175 m下降至145 m再叠加50 a一遇强降雨时为滑坡最危险工况;滑坡变形趋于基本稳定的成果。

After the completion of the Three Gorges reservoir area, geological conditions have changed significantly with a number of landslides under the influence of cyclical water fluctuations. Some landslides were so close to instability that if the area suffered from heavy rainfall and decreasing water level at the same time, it would likely become unstable. This article used the large general-p~ finite element software ABAQUS to calculate fluid - solid coupling in a landslide in the Three Gorges reservoir area under the condition of water level decline and rainfall, and analyzed the changes of the stress and displacement field. Horizontal displacement data were extracted as basis for landslide prediction. Results show that the decline of reservoir water level from 175m to 145m together with once-in-50-year rainfall intensity is the most dangerous condition for landslides; landslide deformation tends to be basically stable.