降雨入渗对残积土填坡渗流变形数值模拟分析

许多研究已经证实了降雨引起的渗流能降低填土稳定性，特别是对于非饱和残积填土。降雨能使残积填土内形成渗流潜蚀破坏，并使地下水位和孔隙水压力发生变化，导致抗剪强度下降形成潜在破坏面，最终发生破坏。利用有限元数值分析，研究等降雨强度与降雨持续时间对于福建地区残积填土的影响，发现降雨强度变大或持续时间延长都能使残积填土内的地下水位上升，局部区域孔隙水压力增大，渗流速率也发生变化，从而影响残积填土的稳定性。另外，证实了存在降雨临界持续时间，一旦降雨持续时间超过了临界持续时间，地下水位线高度随降雨持续时间变长而降低，安全系数就转而变大。

Numerical analysis of rainfall-induced transient seepage in filled residual soil

Many studies have indicated that the infiltration of rainfall can decrease the stability of filled soil, especially for the unsaturated filled residual soil. Rainfall leads to transient seepage and raise the groundwater level, resulting in an increase of pore water pressure and a decrease of shear strength on the potential failure surface and then failure occurs. To investigate the influence of rainfall intensity and duration on filled residual soil in Fujian region, a parametric study has been conducted using the finite element method. The results show that an increase of rainfall intensity or duration causes an raising of groundwater and change of pore water pressure and seepage velocity, so as to result in the decrease of filled residual soil stability. However, a critical rainfall duration can be identified for such filled residual soil, at which the safety factor is the lowest.