考虑初始渗流场影响的坡积土边坡降雨入渗过程
Process of rainfall infiltration of residual slope considering the effect on initial seepage field

为了研究初始渗流场的分布对坡积土边坡降雨入渗的影响,基于饱和？卜潜ズ蜕？流计算原理，采用能同时考虑饱和渗流与非饱和渗流的有限元数值模拟方法，分别对4种初始渗流场影响下边坡的降雨入渗过程进行了模拟计算。研究结果表明：降雨期间，入渗影响区内孔隙水压力、含水率的响应时间、达到暂态饱和区的时间与距坡面的距离成反比，进入暂态饱和区的长度及增大幅度与降雨强度成正比；降雨停止后，暂态饱和区内孔隙水压力、含水率消散所需时间与降雨强度成正比，入渗影响区与暂态饱和区之间孔隙水压力、含水率先增大后缓慢降低，入渗影响区外孔隙水压力、含水率保持不变；降雨引起边坡内部孔隙水压力及含水率的增大，增大幅度与降雨强度呈正比例关系，在降雨强度相同的条件下，初始基质吸力越大，雨水入渗难度越大；在最大初始基质吸力相同，而初始渗流场的分布形式不同时，初始渗流场水平等值分布的边坡更不易于雨水入渗；降雨过程中，暂态饱和区出现时间、深度及面积与降雨强度成正比，降雨停止后，暂态饱和区深度及面积逐渐消散，边坡内部孔隙水压力、含水率、暂态饱和区的分布与降雨强度、初始渗流场最大基质吸力以及分布形式密切相关，选择合适的初始渗流场是进行边坡降雨入渗过程研究的前提条件。
In order to study the influence of initial seepage field distribution on rainfall infiltration of residual slope. Based on the theory of saturated unsaturated seepage, and adopting by finite element numerical simulation method which can simultaneously consider saturated seepage and unsaturated seepage, the infiltration process of slope under the influence of four initial seepage fields is simulated, respectively. The results show that during rainfall, infiltration zone pore water pressure, the response time of moisture content, and time to reach transient saturated zone is inversely proportional to the distance from the slope, while the length of the transient saturated zone and the rate of increase are proportional to the intensity of the rainfall. After the rain, transient saturated zone pore water pressure and the time required for the dissipation of water content are proportional to the intensity of rainfall. Pore water pressure and water content between infiltration affected zone and transient saturated zone increase firstly and then decrease slowly. Water pressure and water rates remain unchanged outside the infiltration effect zone. Rain will cause the increase of pore water pressure and moisture content of in side slope, and its increase magnitude is directly proportional to rainfall intensity. Under the same condition of rainfall intensity, the greater the initial matric suction, the more difficult the rainwater infiltration. Under the same maximum initial matric suction and the different distribution of initial seepage field, the rain is harder infiltrating to the slope whose initial seepage field is horizontal contour distribution. During rainfall, the appeared time, depth and area is proportional to rainfall intensity. After the rain, depth and area of transient saturated zone gradually dissipate. Pore water pressure, water content and distribution of transient saturated zone of slope are closely related to rainfall intensity, the maximum matrix suction of initial seepage field and the distribution form. The prerequisite for