中文摘要：

基于非饱和渗流理论,运用有限元渗流分析软件,模拟了降水作用下田家院子滑坡瞬态渗流场的变化,对滑坡进行了稳定性计算分析,研究了短期降水、持续降水作用下非饱和土边坡稳定性变化规律,计算结果表明：降水时长为2 d时,滑坡稳定性系数在降水期间急剧下降,降水后经历波动调整,最后以每天约0.01的趋势上升;降水持续时间为5 d时,滑坡稳定性系数在降水后期下降速度变缓甚至保持平稳状态。引入饱水面积比的概念,探讨了降水时非饱和土边坡的稳定性系数与地下水位之间的关系,结果表明：滑坡稳定性系数随滑坡体剖面饱水面积比的增大而减小,两者之间呈线性关系,当饱水面积比为0.49时,田家院子滑坡处于极限平衡状态。

英文摘要：

Based on the unsaturated seepage theory, Tianjiayuanzi landslide was taken as an example to simulate the changes of transient seepage field of unsaturated soil slope under rainfall effects by the finite element seepage analysis software and a stability calculation analysis on landslide was also carried out. The study on the change law of unsaturated soil slope stability under short-term rainfall effects and continuous rainfall effects was conducted by the paper. The results show that when the rain lasts two days, the landslide stability coefficient declines sharply during the rainfall and after the rainfall it goes through fluctuation adjustment firstly and then it is on the rising trend with a increase of 0.01 every day; when the rain lasts five days, the landslide stability coefficient declines slowly and even keeps in steady state at the late stage of rainfall. The saturation-area ratio is introduced to discuss the relationship between landslide stability coefficient and phreatic line under rainfall effects. The landslide is in the state of limit equilibrium when the saturation-area ratio is 0.49.