基于ABAQUS强度折减法分析库水位下降对边坡稳定性影响

Analysis of Influence of Drawdown of Reservoir Water Level on Landslide Stability Using Strength Reduction Method Based on ABAQUS

三峡水库自运行以来,库水下降成为滑坡复活的一个诱因.本文根据库区水位调度方案,利用ABAQUS软件模拟库水位在175～145m的下降过程,考虑饱和-非饱和渗流场与应力场耦合理论效应,并采用强度折减法分析库水下降对树坪滑坡稳定性的影响.分析结果表明:三峡水库以0.21m/d的速度由175m降至145m时,树坪滑坡前缘会产生一定的变形,滑坡后缘和中部,基本上未产生变形,目前树坪滑坡处于较稳定状态,但在库水反复变动及降雨作用下,可能会面临失稳的危险.其成果将为库区滑坡治理提供一定的理论依据.

Reservoir water level drawdown has become an inducing factor that affect the landslides which have reactivated since the reservoir impounding. According to the water scheduling solution in reservoir, using ABAQUS software to simulate the water level drawdown process of 175--;145 m, considering the case of nu- merical method based on coupling theory of unsaturated-saturated seepage-stress field and stress field coupling theory effect. By using the strength reduction method, the effect on the stability of Shuping landslide is analyzed. The results show that： when the water lever of reservoir reduced from 175 m down to 145 m with the speed of 0.21 m/d, the front of Shuping landslide will produce some deformation, while there＇s basically no deformation in the back and centre. The Shuping landslide is in stable state at present, but with the repeated change in reservoir water level and rainfall, it could face the risk of instability. The research results will provide theoretical basis for landslide treatment design.