滑面极径-应力-强度耦合关联下非线性破坏特征边坡稳定性极限平衡分析方法  

Limit equilibrium method for analyzing slope stability with nonlinear failure characteristics considering the coupling relationship of polar diameter,stress,and strength of the slip surface

作　　者：邓东平[1] 彭一航 柳梦琦 李媛媛 DENG Dong-ping;PENG Yi-hang;LIU Meng-qi;LI Yuan-yuan(College of Civil Engineering,Central South University,Changsha,Hunan 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙400075

出　　处：《岩土力学》2024年第11期3235-3258,共24页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52278380);湖南省自然科学基金(No.2023JJ30670)。

摘　　要：非线性强度准则下边坡破坏模式、滑面应力以及岩土剪切强度参数存在耦合关联,从而加大了边坡稳定性分析与最可能破坏模式揭示的难度。为此,以滑面应力计算模式代替条块划分下条间力假设模式,并嵌入非线性Mohr-Coulomb(简称M-C)强度准则以及引入滑面端部应力约束条件。在此基础上,结合滑体整体力学平衡条件,建立滑面应力计算模式下非线性破坏特征边坡稳定性极限平衡解答。与此同时,依据现有滑面模型,将滑面概化为旋转中心点下极径与极角所表征的曲线,以此构建通用型滑面生成模型。进一步,针对分层边坡,提出合理的“应力连续+最不利剪切方向”层间滑面连接模式。随后,采取滑面极径-应力-强度联合迭代法,整合滑面应力计算模式下边坡稳定性极限平衡解答与通用滑面生成模型,实现非线性强度准则下边坡稳定性有效分析与最可能失效模式可靠揭示。通过多个边坡算例对比分析,此方法的可行性得以验证,而且当前研究工作将有利于进一步探明非线性强度准则下边坡破坏机制。The analysis of slope stability under a nonlinear strength criterion presents significant challenges due to the coupling of slope failure modes,stress distribution on the slip surface,and soil strength parameters.In this study,these challenges are addressed by employing a stress-based calculation mode for the slip surface,as opposed to the assumption of inter-slice forces under the slice division.Additionally,the nonlinear Mohr-Coulomb(M-C)strength criterion is incorporated,and stress constraint conditions at both ends of the slip surface are introduced.This,along with the global mechanical equilibrium conditions of the sliding body,establishes a limit equilibrium solution for slope stability with nonlinear failure characteristics using the stress-based calculation model for the slip surface.Furthermore,the slip surface is generalized to a curve represented by the polar diameter and polar angle under the rotating center point,creating a generalized generation model of the slip surface.For layered slopes,a rational connection mode for the inter-layer slip surfaces is proposed based on the most unfavorable shear direction under continuous stress.To integrate the limit equilibrium solution of slope stability under the stress-based calculation mode for the slip surface and the generalized generation of the slip surface,a joint iterative method for the polar diameter,stress,and strength of the slip surface is adopted.Through the comparison and analysis of several slope cases,the feasibility of the present method is verified,and the current work has the potential to contribute to a deeper understanding of slope failure mechanisms under the nonlinear strength criterion.

关 键 词：边坡稳定性 极限平衡 非线性M-C强度准则 滑面极径-应力-强度耦合关联关系 通用型滑面模型 滑面应力函数 

分 类 号：TU457[建筑科学—岩土工程]