考虑Hoek-Brown破坏准则的圆形隧道支护结构内力分析  

Internal forces of analysis circular tunnel supporting structure considering Hoek-Brown failure criterion

作　　者：杜佃春 郭鹏 DU Dianchun;GUO Peng(Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education,Southeast University,Nanjing 211189,China)

机构地区：[1]东南大学混凝土及预应力混凝土结构教育部重点实验室,江苏南京211189

出　　处：《铁道科学与工程学报》2022年第8期2330-2338,共9页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(52108305);江苏省自然科学基金资助项目(BK20210256);江苏省双创博士项目(JSSCBS20210068)。

摘　　要：现有研究中,可高效地给出考虑Hoek-Brown破坏准则的圆形隧道衬砌结构内力分布规律的研究方法较少。为探究考虑Hoek-Brown破坏准则时的圆形隧道支护结构内力分布规律,基于超静定响应法,通过将Hoek-Brown破坏准则中的岩石强度参数转化为等效Mohr-Coulomb强度参数,给出考虑Hoek-Brown破坏准则的圆形隧道支护结构内力计算方法。通过将本文方法所得结果与经典解析解答进行对比,验证方法的有效性。利用给出的弯矩和轴力的计算表达式,探究了不同的隧道埋深H,不同的岩石无侧限抗压强度σci和地质强度参数GSI对隧道支护结构内力分布的影响规律。研究发现:参数H,σci和GSI对圆形衬砌结构内力影响较大,衬砌结构的弯矩和轴力值随H的增加而增长,但随σci和GSI的增加而减小;隧道开挖后岩石完整越好,围岩的整体自稳定性越好,使得衬砌结构内力越小。衬砌结构弯矩绝对值的最大值出现在隧道拱顶、侧墙和拱底处,而轴力绝对值的最大值仅出现在侧墙处。给出的方法既可为隧道设计初期支护结构的力学行为分析提供参考,又能为在服从Hoek-Brown破坏准则的岩体中开挖的圆形隧道支护结构设计提供理论参考。In the existing research studies,there are few research methods that can efficiently give the internal force distribution law of circular tunnel lining structure considering Hoek Brown failure criterion.Therefore,based on the Hyperstatic Reaction Method,the internal force distribution of a circular tunnel lining in the rock masses obeying the Hoek-Brown failure criterion was explored by transforming the rock strength parameters that obey the Hoek-Brown failure criterion into the equivalent Mohr-Coulomb strength parameters.After comparing with the analytical values and verifying the present method,the influence of different tunnel depths H,different rock unconfined compressive strengthσci and geological strength parameter GSI on the behavior of tunnel lining was investigated in terms of bending moments and normal forces.It is found that the parameters H,σci and GSI have a significant effect on the internal forces of the circular tunnel lining.The bending moments and normal forces of the lining increase with the increase of H but decrease as theσci and GSI increase.This is because higher GSI values represent lower discontinuities and better rock mass surface conditions,and the integrity and selfstability of the excavated rock masses are therefore better.The maximum absolute value of the bending moment appears at the crown,sidewall and invert arch of the tunnel,while the maximum absolute value of the axial force appears at the side wall.The present method could be able to provide a theoretical reference for the design of the circular tunnel support structure in the rock masses following the Hoek-Brown failure criterion.

关 键 词：Hoek-Brown破坏准则 圆形隧道 结构内力 超静定响应法 等效Mohr-Coulomb强度参数 

分 类 号：U25[交通运输工程—道路与铁道工程]