考虑土层软化及渗流应力耦合的边坡稳定性分析  

Slope stability analysis considering soil softening and seepage-stress coupling effect

作　　者：彭和鹏 李馨馨 PENG Hepeng;LI Xinxin(Anhui Simashan Diversion Project Management Office,Maanshan 238251,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China)

机构地区：[1]安徽省驷马山引江工程管理处,安徽马鞍山238251 [2]中国地质大学(武汉),湖北武汉430074

出　　处：《武汉大学学报（工学版）》2022年第2期117-122,共6页Engineering Journal of Wuhan University

摘　　要：为合理评价地下水对边坡稳定性的影响,采用有限元法对考虑土层遇水软化及渗流应力耦合效应的边坡稳定性进行分析,基于空气单元法求解含排水井边坡的多重非线性渗流场,基于强度折减法确定最危险滑动面和稳定安全系数。结合驷马山分洪道工程切岭段右岸边坡,开展渗流、应力及稳定性分析,得到边坡中的水头、应力分布及变形特征;评价了边坡布设排水井措施对其稳定性的影响。结果表明:水的渗流及软化作用是导致滑坡的重要影响因素,该方法可为分析排水条件下边坡可能的破坏形式及稳定安全性提供依据;计算所得浸润面和溢出点结果都符合一般规律,该方法可以有效模拟排水井的排水降压效果;切岭段右岸边坡采取减压排水井的治理措施后,边坡稳定安全系数由1.146提高到1.266,满足规范设计要求。本研究成果对类似边坡工程的稳定分析及治理措施具有一定的借鉴意义。In order to reasonably evaluate the influence of groundwater on slope stability, the finite element method is used to analyze the stability of soil slope considering coupling effect of soil softening and seepage stress coupling. The multiple nonlinear seepage field of slope containing drainage wells is simulated based on air element method. The potential sliding surface and stability safety factor are determined by the strength reduction method. The seepage, stress and stability analysis of the right bank slope of the Qieling section of the Simashan Flood Diversion Project are carried out to obtain the head, stress distribution and deformation characteristics.The influence of the drainage well on the stability of the slope is also evaluated. The results show that soil softening and water seepage are important factors leading to landslides, and the developed method can provide a basis for the possible failure mode and failure process of slopes with drainage wells. The results of the calculated free surface and overflow points are consistent with the general laws. The developed approach can effectively simulate the drainage and depressurization effect of the drainage wells. After applying the slope treatment measures of the drainage wells, the safety factor of the slope stability of the right bank of the Qieling section increases from 1.146 to 1.266, meeting the requirements of the normative design. The research results have a certain reference for stability analysis and control measures of similar slope engineering.

关 键 词：边坡稳定性分析 有限单元法 渗流应力耦合 强度折减法 安全系数 

分 类 号：TU43[建筑科学—岩土工程]