降雨入渗对边坡稳定影响的数值模拟研究

根据粉细砂边坡的饱和一非饱和强度与渗流理论，通过数值模拟方法研究降雨入渗对边坡稳定性的影响。数值模拟结果揭示了对边坡变形和破坏的作用机理，表明降雨是诱发滑坡的关键因素之一；粉细砂边坡在无降雨时基本处于稳定状态，连续性降雨使边坡土体的含水量显著增加，坡脚部位饱和区内的基质吸力减小并出现塑性区，随着降雨历时延长，饱和区逐渐扩展至边坡土体中部，塑性区逐渐扩展直至贯通而发生滑坡；在长期低强度降雨条件下边坡较易发生深层滑动，强降雨时边坡更易发生浅层滑动。该研究提出了降雨条件下边坡的稳定性分析供一般的技术思路，可供边坡失稳预警和滑坡防治参考。

Numerical Simulation on Slope Stability under Rainfall Infiltration

According to the saturated/non-saturated strength and infiltration theory of silty fine sand slope, numerical simulation method is used to study the stability of slope under rainfall infiltration. The research results show the slope deformation and damage mechanism, and rainfall is one of key factors to induce landslide. The stability of silty fine sand slope can be decreased under rainfall. Continuous rainfall increases soil water content of the slope significantly, decreases matric suction of the saturated zone at base of slope and plastic zones occur. When rainfall duration is longer, the saturated zone gradually extends to central soil body of the slope, and the plastic zones gradually extend and interconnect each other, thus landslide occurs. The slope＇ s deep sliding occurs easily under long low-intensity rainfall, and the shallow sliding under heavy rainfall. In the above research, general technical ideas are put forward to analyze stability of the slope under rainfall, which will provide references for early warning of slope instability as well as landslide prevention and cure.