基于渐进破坏理论的顺层岩质边坡稳定性解析  

Stability analysis of bedding rock slope based on progressive failure theory

作　　者：向波 蒋金谷 张乐 张俊云[3] 冯君[3] 邬凯[1] XIANG Bo;JIANG Jingu;ZHANG Le;ZHANG Junyun;FENG Jun;WU Kai(Sichuan Highway Planning,Survey,Design and Research Institute Ltd,Chengdu 610041,China;Chengdu Construction Engineering Group,Chengdu 610014,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]四川省公路规划勘察设计研究院有限公司,四川成都610041 [2]成都建工集团,四川成都610014 [3]西南交通大学土木工程学院,四川成都610031

出　　处：《自然灾害学报》2024年第6期37-47,共11页Journal of Natural Disasters

基　　金：四川省交通运输科技项目(2021-A-02);四川省科技计划重点项目(2021YFS0321)。

摘　　要：顺层岩质边坡的坡脚开挖扰动后易发生牵引式失稳滑移。为研究不同破坏阶段的顺层岩质边坡稳定性,采用半无限楔形体模型计算坡体开挖面应力,然后赋予滑面陡降型应变软化模型,对不同破坏阶段顺层岩质边坡的开挖释放应力、滑面应力状态、滑面位移和边坡稳定系数等状态特征进行量化解析,形成了临界荷载求解、渐进破坏阶段界定和稳定系数解析3步走的系统解析流程;探讨了顺层岩质边坡首次滑移长度的确定方法,最后通过工程实例进行分析验证。结果表明,顺层岩质边坡的渐进破坏可划分为峰前应力阶段、峰前-残余应力阶段和残余应力阶段;提出不同阶段的稳定系数解析方法,建立了顺层岩质边坡首次滑移长度的应力计算式。首次滑移长度参考值较实际值相差9.3%,所得解析结果可为工程设计提供参考。Traction instability slip is prone to occur after excavation disturbance at the toe of bedding rock slope.To study the stability of bedding rock slope at different failure stages,the semi-infinite wedge model was used to calculate the stress of the excavation face of the slope.Then the strain softening model of sliding surface steep drop type was given.The state characteristics of excavation release stress,sliding surface stress state,sliding surface displacement and slope stability coefficient of bedding rock slope in different failure stages were quantitatively analyzed,and a three-step systematic analytical process for solving critical load,defining progressive failure stage,and analyzing stability coefficient is formed.Furthermore,the determination method of the initial slip length of bedding rock slope was addressed.Finally,the analysis was verified by engineering examples.The results show that the instability failure of bedding rock slope may be divided into the pre-peak stress,pre-peak-residual stress and residual stress stage.The analytical method of stability coefficient at different stages is proposed.The stress calculation formula of the first slip length of bedding rock slope is also established.The reference value of the initial slip length determined by the progressive failure mechanics model is 9.3%different from the actual one.The analytical results may provide a reliable reference for engineering design.

关 键 词：顺层岩质边坡 渐进破坏理论 稳定系数 首次滑移长度 力学解析 

分 类 号：TU457[建筑科学—岩土工程] X43[建筑科学—土工工程]