隧底围岩损伤条件下隧道结构动力响应及疲劳寿命研究  

Study on Dynamic Response and Fatigue Life of Tunnel Under Damaged Surrounding Rock Conditions

作　　者：兰毅 王登科 文绍全 LAN Yi;WANG Dengke;WEN Shaoquan(China Railway 2nd Engineering Group Co.,Ltd.,Chengdu 610031,China;Beijing Infrastructure Investment Co.,Ltd.,Beijing 100101,China;Beijing MTR Construction Administration Corporation,Beijing 100068,China;Department of Civil Engineering,Tsinghua University,Beijing 100084,China;Yunnan Water Conservancy and Hydropower Construction Management and Quality Safety Center,Kunming 650224,China)

机构地区：[1]中铁二院工程集团有限责任公司,四川成都610031 [2]北京市基础设施投资有限公司,北京100101 [3]北京市轨道交通建设管理有限公司,北京100068 [4]清华大学土木工程系,北京100084 [5]云南省水利水电建设管理与质量安全中心,云南昆明650224

出　　处：《国防交通工程与技术》2024年第4期14-20,共7页Traffic Engineering and Technology for National Defence

摘　　要：为研究隧底围岩软化、脱空下隧道结构的动力响应特性,结合现场测试和数值模拟,使用有限差分软件建立了数值模型,分析了隧底结构竖向位移、竖向加速度和主应力响应特征,预测了不同工况下隧底结构服役寿命。结果表明:随着隧底围岩软化系数的减小和脱空宽度的增加,结构的动力响应均呈现不同程度的增大;隧底结构服役寿命主要受抗拉强度的影响,最不利位置为轨下仰拱处。为便于工程实践中的安全管理与维护决策,将隧底结构疲劳寿命分为安全、警示、危险、严重危险四个等级,软化系数为0.6时或者脱空宽度为2.0 m时,隧底结构处于危险区,需立即采取措施进行整治。相关研究为保障重载铁路隧道的运行安全提供了坚实的理论支撑和实用指导。To study the dynamic response characteristics of tunnel structures under the softening and void of the surrounding rock at the bottom of the tunnel,a refined numerical model was developed in finite difference software combined with field-measured data.The paper analyzed the vertical displacement,vertical acceleration,and principal stress response characteristics of the tunnel bottom structure under different conditions,providing a reasonable prediction of its service life.The analysis results show that the gradual decrease in the softening coefficient of tunnel surrounding rock and the continuous expansion of void width will both lead to significant changes in the structural dynamic response.Further analysis indicates that the service life of the tunnel bottom structure is mainly affected by tensile strength,with the sub-rail inverted arch being the most weakest point.For practical safety management and maintenance decisions in engineering,the fatigue life of the tunnel bottom structure is divided into four levels:safe,caution,danger,and severe danger.Specifically,when the softening coefficient of the tunnel surrounding rock falls below 0.6 or the void width reaches 2.0 m,the tunnel bottom structure is considered to be in a dangerous state,necessitating immediate remedial measures.This study provides a solid theoretical basis and practical guidance for ensuring the safe operation of heavy-duty railway tunnels.

关 键 词：重载铁路隧道 隧底围岩损伤 列车振动荷载 动力响应 数值模拟 

分 类 号：U451[建筑科学—桥梁与隧道工程]