基于零厚度粘聚力单元的降雨入渗下岩质边坡稳定性分析

Stability Analysis of Rock Slope under Rainfall Infiltration Based on A Zero-Thickness Cohesive Element

岩质边坡往往存在着大量节理、裂隙等过水通道, 短时强降雨或持续降雨条件下雨水大量进入坡体, 极易诱发岩质边坡发生滑坡灾害, 因此研究降雨入渗作用下岩质边坡的稳定性具有重要意义。本文以ABAQUS数值仿真平台为基础, 通过嵌入零厚度粘聚力单元实现降雨条件下岩质边坡变形破坏过程的连续-非连续模拟, 以矢量和法安全系数为衡量指标, 重点研究降雨强度、降雨时长和降雨入渗位置对边坡稳定性的影响。结果表明: 随着降雨强度和降雨时长的增大, 边坡体内裂隙深度逐渐变大, 边坡稳定性逐渐降低; 降雨入渗的初始位置距离坡肩越远, 降雨诱发的裂隙延伸长度就越短, 边坡稳定性越好。研究结果为降雨条件下岩质边坡工程治理提供参考。

There are often a large number of joints, fissures and other water channels in rock slopes. Under the condition of short-term heavy rainfall or continuous rainfall, a large amount of rainwater enters the slope body, which can easily induce landslide disaster on rock slopes. Therefore, it is of great significance to study the stability of rock slope under the infiltration of rainfall. Based on the ABAQUS numerical simulation platform, this paper implements continuous-discontinuous simulation of the deformation and damage of rock slopes under rainfall conditions by embedding zero-thickness cohesive elements and focuses on the effects of rainfall intensity, rainfall duration and rainfall infiltration location on the slope stability using vector method safety factors as indicators. The results show that as the rainfall intensity and rainfall duration increase, the depth of fissures in the slope gradually becomes larger, and the stability of the slope gradually decreases. The farther the initial location of rainfall infiltration is from the shoulder of the slope, the shorter the rain-induced fissure extension length is and the better the stability of the slope is. The research results provide reference for the engineering treatment of rock slope under rainfall conditions.