降雨条件下动力荷载对边坡长期稳定的影响研究

Influence of Dynamic Load on Long Term Stability of Slope under Rainfall Condition

针对在降雨和交通荷载共同作用下边坡的长期稳定问题,通过路堤模型试验,研究降雨条件下边坡动力响应的变化规律,根据基质吸力、体积含水率、土压力的变化情况来反映边坡稳定性的变化。研究结果表明,在降雨条件和动力荷载作用下,雨水由坡面向坡体内部渗入,在持续的降雨条件下,坡表径流在坡顶处雨水入渗量较少,大部分沿着边坡表面流向坡脚,使坡脚处土体入渗情况较为严重;而路堤边坡的坡前应力逐渐增大,当停止降雨后,其增速呈现出先减慢后减小最终逐渐稳定的趋势;在停止降雨后,随着基质吸力的恢复,雨水深入边坡土体,其坡面孔隙水压力逐渐消散,坡体内暂态饱和区也渐渐减小。通过上述研究分析,以期为现有边坡稳定性设计提供参考。

In view of the long-term stability of slope under the combined action of rainfall and traffic load,this study studies the change law of slope dynamic response under the condition of rainfall through embankment model test,and reflects the change of slope stability according to the changes of matrix suction,volume moisture content and soil pressure.The results show that under the rainfall condition and dynamic load,the rainwater infiltrates from the slope to the interior of the slope.Under the continuous rainfall condition,the rainwater infiltration amount of the runoff on the slope surface is less at the top of the slope,and most of it flows along the surface of the slope to the foot of the slope,which makes the soil infiltration at the foot of the slope more serious;the stress in front of the embankment slope increases gradually.When the rainfall stops,the growth rate first slows down,then decreases,and finally becomes stable;after stopping the rainfall,with the recovery of the matric suction,the rainwater penetrates into the slope soil,the pore water pressure of the slope surface gradually dissipates,and the transient saturation area of the slope body gradually decreases.Through the above research and analysis,in order to provide reference for the existing slope stability design.