张拉-剪切破坏模式下边坡三维临界滑面的Cauchy问题  

Cauchy problem of three-dimensional critical slip surface of slope under tension-shear failure mode

作　　者：王娇 林姗 罗柳 郑宏 孙冠华[1,2] 龙万学 WANG Jiao;LIN Shan;LUO Liu;ZHENG Hong;SUN Guan-hua;LONG Wan-xue(State Key Laboratory of Geotechnical Mechanics and Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Key Laboratory of Urban Security and Disaster Engineering,Ministry of Education,Beijing University of Technology,Beijing 100124,China;The First Engineering Company Limited of the Second Harbor Engineering,Wuhan Hubei 430056,China;Guizhou Transportation Planning Survey&Design Academe Co.,Ltd.,Guiyang,Guizhou 550001,China)

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071 [2]中国科学院大学,北京100049 [3]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [4]中交二航局第一工程有限公司,湖北武汉430056 [5]贵州省交通规划勘察设计研究院股份有限公司,贵州贵阳550001

出　　处：《岩土力学》2022年第9期2634-2642,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.11972043);国家重点研发计划(No.2018YFE0100100);贵阳市轨道交通1号线工程科研课题“近邻深基坑开发项目对城市轨道交通结构影响机制与控制措施研究”。

摘　　要：边坡失稳常表现为压剪-张拉破坏等复杂形态。基于有限元-强度折减法,获得边坡的极限应力场和应变场,从三维边坡的极限应力场出发,考虑剪切-张拉两种破坏模式,将边坡临界滑面定位问题转化为求解一阶拟线性偏微分方程的初值问题,即Cauchy问题。在边坡后缘等拉应力区采用张拉破坏模式,在被动滑动区域采用Mohr-Coulomb屈服准则的剪切破坏模式,在未假定滑面几何形式和未指定滑动模式的前提下自动确定临界滑面。分别研究了缓倾结构面的三维边坡和陡倾结构面的三维边坡,描述了二者的几何特征和分布形态,并与无节理均质边坡进行了对比分析。结合物理模型试验,开展了均布荷载作用下均质边坡在极限应力状态下的破坏特征研究,验证了方法的正确性和可靠性。The failure mechanism of slope instability is complex,and the characteristics of sliding surface often show complex forms such as compression shear-tension failure.Based on the finite element strength reduction method,the limit stress field and strain field of slope are obtained.Starting from the limit stress field of three-dimensional slope,and considering tension-shear composite failure,the positioning problem of slope critical sliding surface is transformed into the initial value problem for solving the first-order quasilinear partial differential equation,namely,the Cauchy problem.The tensile failure mode is adopted in the equal tensile stress area at the scarp of the slope,and the shear failure mode of Mohr-Coulomb yield criterion is adopted in the passive sliding area.In this way,the critical slip surface is determined without assuming the geometry of the slip surface and specifying the slip mode automatically.The three-dimensional slope of gently inclined structural plane and steeply inclined structural plane are studied respectively.Not only the geometric characteristics and distribution of the two are described,but also compared with the jointed homogeneous slope.Finally,combined with the physical model test,the failure characteristics of homogeneous slope under uniformly distributed load in ultimate stress state are studied to verify the correctness and reliability of the method.

关 键 词：张拉-剪切复合破坏 三维节理边坡 临界滑面 

分 类 号：TU457[建筑科学—岩土工程]