降雨入渗条件下斜坡高填方路基稳定性分析

Stability Analysis of High Fill Subgrade of Slope under Rainfall Infiltration Condition

以贵州省某高速公路一高填方路段斜坡为研究对象,以非饱和渗流理论为基础,根据当地实际的降雨情况和雨型特点,采用有限元分析方法对边坡的渗流情况和稳定性进行模拟分析。结果表明:该斜坡设计较为合理,排水泄水能力较强,在该地小到中型的连阴雨特点的情况下,斜坡稳定性变化不大;随降雨入渗开始,斜坡稳定性下降速率随降雨时间的增加而不断增大,降雨停止时达到最低,说明坡体本身排水泄水能力较强,降雨的滞后性体现不明显;降雨停止后,斜坡稳定性开始缓慢恢复,但其恢复速率远小于降雨时下降的速率。

Based on the slope of the high fill section of an expressway in Guizhou province, based on the theory of unsaturated seepage, in accordance with the local actual rainfall conditions and rain patterns, this paper used the finite element analysis method to simulate the situation of seepage and the slope stability. The result showed that the design of this slope was reasonable and its drainage and weepage capacity was strong. Under the condition of the local small to medium-sized continuous rainy rainfall, the slope stability did not change much;with the start of the rainfall infiltration, the lowering speed of the slope stability continued to enlarge with the increase of the rainfall time, and reached the lowest when the rainfall stopped. This indicated that the slope itself had strong drainage and weepage capacity, and the hysteresis of rainfall was not obvious. After the rainfall stopped, the slope stability began to recover slowly, but its recovery rate was much smaller than the lowering rate during rainfall.