含软弱夹层顺层岩质边坡开挖稳定性分析  

Analysis of Stability in Excavation of Rock Bedding Slope Containing Weak Intercalations

作　　者：刘品[1] 陈权川 龙维 LIU Pin;CHEN Quanchuan;LONG Wei(Guizhou Transportation Planning Survey&Design Academe Co.,Ltd.,Guiyang 550081,China;Guizhou Institute of Technology,Guiyang 550003,China)

机构地区：[1]贵州省交通规划勘察设计研究院股份有限公司,贵阳550081 [2]贵州理工学院,贵阳550003

出　　处：《路基工程》2024年第4期171-176,共6页Subgrade Engineering

摘　　要：以都安高速公路某段含软弱夹层顺层岩质边坡为例,采用极限平衡法对开挖后的边坡进行稳定性分析,基于FLAC3D软件模拟分析边坡分级开挖、分级支护过程中的位移、最大剪切应变增量、应力特征及抗滑桩的承载性能。结果表明:严格条分法的安全系数为1.011,强度折减法安全系数为条分法的97.13%,当考虑岩土体变形时,传统计算方法可能会高估边坡自身的稳定性;边坡采用抗滑桩+框架锚索+框架锚杆的联合支护方式,并进行分步开挖及分级支护,对坡体扰动小,支护效果良好,能很好地控制坡体变形,避免边坡因软弱夹层塑性区贯通而发生失稳破坏。Taking a section of rock bedding slope containing weak intercalations along Du'an Highway as an example,limit equilibrium method was used to analyze the stability of the excavated slope.On the basis of the simulation with FLAC3D software,the displacement,the maximum shear strain increment,the stress feature and the bearing capacity of anti-sliding piles in the course of step supported excavation,were analyzed.The results show that,the safety coefficient of strict slice method is 1.011,and that of strength reduction method is 97.13% of slice method.When the deformation of rock and earth mass is considered,the traditional calculation method may give overvalue of the slope stability.The slope is adopted the combined support mode of anti-sliding piles+anchor cable frame+anchor bolt frame,and then supported and excavated in steps,thus small disturbance is caused to the slope and good supporting effect is obtained.As a result,the slope deformation may be under control and it can prevent the slope from failure due to penetration of plastic zone in weak intercalations.

关 键 词：软弱夹层 顺层边坡 强度折减法 极限平衡法 抗滑桩 锚索 联合支护 稳定性 

分 类 号：U416.14[交通运输工程—道路与铁道工程]