地下水位上升下黄土斜坡稳定性分析

黄土高原一些地区,由于塬上引水灌溉使得地下水位不断抬升,造成黄土滑坡频繁发生。地下水位变化严重影响着黄土斜坡的稳定性。基于饱和-非饱和渗流理论和延伸的摩尔-库伦破坏准则,结合室内饱和和非饱和试验结果,针对泾阳南塬一典型黄土斜坡,考虑地下水位上升情况下,对其进行了瞬态饱和-非饱和渗流分析;然后将计算得到的瞬态孔隙水压力分布用于斜坡的极限平衡分析。结果表明:地下水位上升对暂态渗流场和斜坡稳定性有明显影响;考虑非饱和渗流和吸力强度的边坡稳定分析方法更加符合实际情况。

ANALYSIS OF LOESS SLOPE STABILITY DUE TO GROUNDWATER RISE

Based on the saturated-unsaturated seepage theory and an extended Mohr-Coulomb failure criterion, combined with the results of saturated and unsaturated triaxial tests, a typical loess slope in the southern tableland of Jingyang County has been adopted for this parametric study. Transient seepage due to water level rise is computed using the finite element method. The computed transient pore water pressures are then used for subsequent limit equilibrium analyses of the slope. The results demonstrate that both transient pore water pressure distribution and slope stability are affected by groundwater level rise. The method involving unsaturated seepage and suction strength is more coincident with the factual data.