强降雨对市政道路高边坡稳定性影响研究--以某市政道路土质边坡为例

Study on the influence of strong rainfall on the stability of high slope of a municipal road

基于非饱和土渗流理论,采用Geo-studio数值模拟软件,分析不同降雨工况下,某市政道路路堤土质边坡分别在降雨前、降雨中、降雨结束后,内部渗流场及边坡稳定性系数的变化规律。结果表明:在强降雨工况下,边坡的基质吸力减小,随着降雨的持续,土质边坡表面会迅速形成暂态饱和区;在渗透系数突变的土层交界面,地下水的向下运移趋势受阻。在降雨停止之后,边坡表面的暂态饱和区逐渐消散,基质吸力逐渐增大。边坡的稳定性系数在整个降雨过程中呈迅速减小的态势;降雨结束后一段时间内,稳定性系数快速回升,之后再次减小并趋于稳定。

Based on unsaturated-soil seepage theory,the changes of internal seepage field and slope stability coefficient of a municipal road embankment during the whole rainfall ephemeris under different rainfall conditions are studied.The results show that under the strong rainfall condition,the matrix suction of the slope decreases,and with the continuation of rainfall,the temporary saturation zone will be formed on the surface of the soil slope rapidly;at the intersection of soil layers with sudden change of permeability coefficient,the downward trend of groundwater transport is blocked.After the rainfall stopped,the instantaneous saturation zone on the slope gradually dissipated,and the matric suction gradually increased.During the whole rainfall process,the stability coefficient of the slope decreased rapidly;for a period of time after the rainfall ends,the stability coefficient rises rapidly,and then decreases and stabilizes again.