考虑余震影响的软岩隧道施工期结构力学特性研究  

Research on Structural Mechanical Characteristics of Soft Rock Tunnel during Construction Period Considering Aftershock Effect

作　　者：杨文波[1,2] 张航 罗春雨[3] 康海波 杜明[3] 杨林霖[1,2] 何川 刘子敬 YANG Wen-bo;ZHANG Hang;LUO Chun-yu;KANG Hai-bo;DU Ming;YANG Lin-lin;HE Chuan;LIU Zi-jing(Key Laboratory of Transportation Tunnel Engineering of Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Branch of Road Tunnel,Sichuan Road and Bridge Construction Co.Ltd.,Chengdu 610200,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,成都市610031 [2]西南交通大学土木工程学院,成都市610031 [3]四川公路桥梁建设集团有限公司公路隧道分公司,成都市610200

出　　处：《公路》2022年第2期281-289,共9页Highway

基　　金：国家自然科学基金面上项目,项目编号51678499。

摘　　要：依托处于强震区复杂应力环境中的典型软岩隧道,通过现场实测数据,首先对静力开挖时隧道结构力学特性进行了分析;并以此为基础结合三维数值仿真分析,进一步研究了不同隧道开挖工法以及在不同施工阶段时隧道余震动力响应规律。研究结果表明:在隧道不同开挖工法下,通过比较余震作用产生的隧道位移差、隧道结构与围岩加速度响应、塑性区和初期支护最小主应力,发现隧道开挖工法对隧道余震动力响应规律影响较小;在隧道开挖不同阶段,即初支单独作用与初支二衬共同作用,二衬的施做使隧道位移差减小17.44%,初支压应力降低16.13%,说明二衬的施做有利于减小余震对隧道造成的不良影响。综合研究结果发现,在复杂应力环境中修建软岩隧道遭遇余震作用时,隧道前方掌子面易发生剪切破坏,隧道结构在拱肩与拱脚处受力较为薄弱,在余震后应为重点观察部位。Relying on a typical soft rock tunnel in a complex stress environment in a strong earthquake zone, through field measured data, the mechanical characteristics of the tunnel structure during static excavation are first analyzed;and on this basis, combined with three-dimensional numerical simulation analysis,the difference of aftershock dynamic response during construction period by different tunnel excavation methods are studied.The study results show that:under different excavation methods,by comparing the tunnel displacement difference,acceleration response of tunnel structure and surrounding rock,plastic zone and minimum principal stress of initial support,it is found that the tunnel excavation method has minor impact on the dynamic response law of tunnel aftershock.In different stages of tunnel excavation,which means the initial support work alone and initial support work together with the lining,the construction of the secondary lining can reduce the tunnel displacement difference by 17.44% and the initial support compressive stress by 16.13%,which indicates that the construction of the secondary lining is conducive to reducing the adverse effects of aftershocks on the tunnel.The conclusions on the study results indicate that when the soft rock tunnel is built in the complex stress environment,the tunnel face is prone to shear failure in front of the tunnel,and the stress of tunnel structure at the arch shoulder and foot is relatively weak,where should be the key observation area after the earthquake.

关 键 词：公路隧道 强震区软岩隧道 余震 结构力学特性 动力时程分析 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]