库岸滑坡变形规律研究

Study on Deformation Characteristics of Reservoir Bank Landslide

以西南长江上游山体库岸滑坡为研究对象,结合边坡所处环境及水库水位情况,研究自然状态和暴雨条件下模型土体渗流、压力及位移变化规律。通过建立试验平台,模拟库岸滑坡实际情况,探究滑坡前缘、中部以及后缘的位移和压力变化情况。结果表明,自然状态下,滑坡位移保持不变,而土压力与孔隙水压力的变化情况呈先减小后增大再减小的交替变化情况。距离水库越近,所受土压力和孔隙水压力越强,地下水渗流也会导致土压力与孔隙水压力减小。地下水位上升导致坡体失去坡体平衡性。在暴雨条件下,模型前缘、中部和后缘位移最大变形量分别为7.8、5.2和3.8mm。且滑坡土压力和孔隙水压力整体增大,但孔隙水压力整体则呈先增大后减小的变化趋势。模型有应力集中和应变能积累现象,其变化规律可为实际工况提供参考与预测。

In this paper,we study the seepage,pressure and displacement changes of the model soil under the natural state and heavy rainfall conditions by taking the upper mountain reservoir bank landslide of the southwest Yangtze River as the research object,and combining the environment where the slope is located and the water level of the reservoir.By establishing a test platform,the actual situation of the reservoir bank landslide is simulated,and the displacement and pressure changes of the front,middle and back edges of the landslide are investigated.The results show that the landslide displacement remains unchanged in the natural state,while the changes of soil pressure and pore water pressure show an alternating change of decreasing,then increasing and then decreasing.The closer to the reservoir,the stronger the soil pressure and pore water pressure,and the groundwater seepage will also lead to the decrease of soil pressure and pore water pressure.The rising groundwater level causes the slope to lose its slope equilibrium.Under heavy rainfall conditions,the maximum deformation of the front,middle and back edges of the model is 7.8,5.2 and 3.8mm,respectively,and the overall increase of soil pressure and pore water pressure of the landslide,but the overall trend of pore water pressure is increasing first and then decreasing.The model has stress concentration and strain energy accumulation phenomenon,and its change law can provide reference and prediction for the actual working condition.