基于PFC-Geostudio耦合的边坡降雨变形破坏研究

Study on Deformation and Failure of Slope Under Rainfall Condition Based on PFC-Geostudio Coupling Method

为研究降雨条件下边坡的变形破坏情况,建立典型边坡模型,通过有限元软件Geostudio进行渗流分析,将不同降雨强度下的边坡土体的含水量情况导入至颗粒流方法中,根据颗粒位置修改其重度、及接触参数,并对渗流区域施加渗流力,当降雨强度大于边坡入渗速度时,增加考虑坡面径流对颗粒的拖曳作用,分析了不同降雨强度下边坡变形情况以及滑坡破坏过程。研究表明,发生降雨时,边坡变形主要为沉降,最大变形产生在坡顶位置;当降雨强度较大时,坡脚颗粒会由于冲刷作用发生滑动,并诱发后部边坡土体发生渐进式牵引式滑坡。

In order to study the deformation and failure of the slope under rainfall conditions,a typical slope model was established,and the seepage analysis was carried out through the finite element software Geostudio.The water content of the slope soil under different rainfall intensities was imported into the particle flow method.The weight and contact parameters of the particles are modified according to the position of the particles,and seepage force is applied to the seepage area.When the rainfall intensity is greater than the maximum infiltration capacity of the slope,the dragging effect of the slope runoff on the particles is added.The deformation of the slope and the failure process of the landslide under different rainfall intensities are analyzed.The results show that when rainfall occurs,the slope deformation is mainly caused by settlement,and the maximum deformation occurs at the top of the slope;When the rainfall intensity is large,the particles at the toe of the slope will slide due to the scouring effect,and the soil mass of the rear slope will be induced to produce a progressive traction landslide.