岩体隧道围岩弹塑性变形条件下管片衬砌支护机理研究  

Study on Support Mechanism of Segment Lining to Rock Tunnel under Elastic-Plastic Deformation of Surrounding Rock

作　　者：史小萌 段云岭[1] 刘保国[2] 王志伟[3] 冯金铭 SHI Xiaomeng;DUAN Yunling;LIU Baoguo;WANG Zhiwei;FENG Jinming(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]北京交通大学土木建筑工程学院,北京100044 [3]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《中国铁道科学》2020年第4期74-81,共8页China Railway Science

基　　金：国家科技支撑计划项目(2013BAB10B06);煤炭开采水资源保护与利用国家重点实验室2018年开放基金课题资助项目(GJNY-18-73.2)。

摘　　要：基于D-P屈服准则的围岩支护作用理论,以隧道掘进机(TBM)施工过程中支护位置与掌子面的距离作为动态参数,综合考虑注浆圈的应力变形特征,构建岩体隧道围岩弹塑性变形条件下围岩、注浆圈和管片衬砌三者动态变形协调方程,提出三者的变形计算方法和管片衬砌围岩压力计算方法,明确管片衬砌对采用TBM开挖的岩体隧道的支护机理。针对新街台格庙岩体隧道工程实例,计算不同支护条件下围岩变形及管片衬砌围岩压力,并通过数值模拟验证理论方法的合理性和有效性。结果表明:如果在掌子面开挖处开始进行支护,管片衬砌围岩压力将达到1.91 MPa,管片安全系数仅为0.76;如果在掌子面后4 m开始进行支护,安全系数将提升至1.25。建议距离掌子面12 m处开始进行支护,可将围岩压力降至0.24 MPa,管片衬砌具有较高的安全系数。Based on the theory of surrounding rock support using D-P yield criterion,the distance between the supporting position and the tunnel face in the construction of Tunnel Boring Machine(TBM)was taken as the dynamic parameter.The stress and deformation characteristics of grouting ring were considered comprehensively.The dynamic deformation coordination equations of surrounding rock,grouting ring and segment lining for rock tunnels under the condition of elastic-plastic deformation of surrounding rock were established.The methods for calculating the deformation of surrounding rock,grouting ring and segment lining as well as for calculating the surrounding rock pressure of segment lining were proposed.The support mechanism of segment lining for rock tunnel excavated by TBM was clarified.According to the engineering example of Taigemiao rock tunnel in Xinjie,the surrounding rock deformation and the surrounding rock pressure of segment lining under different supporting conditions were calculated.The rationality and effectiveness of the theoretical method were verified by numerical simulation.Results show that the surrounding rock pressure of segment lining will reach 1.91 MPa and the safety factor of segment is only 0.76 if the support is started at the excavation of the tunnel face.If the support is started 4 m behind the tunnel face,the safety factor will be increased to 1.25.It is suggested to start the support at 12 m away from the tunnel face,which can reduce the surrounding rock pressure to 0.24 MPa,and the segment lining has a higher safety factor.

关 键 词：岩体隧道 管片衬砌 注浆圈 围岩弹塑性变形 围岩压力 支护机理 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]