黄土地层圆形地铁隧道地震易损性评价  

Seismic fragility assessment of circular metro tunnels in loess deposit

作　　者：孙纬宇 林峻岑 马勤国 严松宏 佟浩 梁庆国 SUN Wei-yu;LIN Jun-cen;MA Qin-guo;YAN Song-hong;TONG Hao;LIANG Qing-guo(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;National and Local Joint Engineering Laboratory for Disaster Prevention and Control Technology of Road and Bridge Engineering,Lanzhou 730070,China;State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China [2]National and Local Joint Engineering Laboratory for Disaster Prevention and Control Technology of Road and Bridge Engineering,Lanzhou 730070,China [3]State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510641,China

出　　处：《Journal of Central South University》2024年第3期950-964,共15页中南大学学报（英文版）

基　　金：Projects(52208392,52068044)supported by the National Natural Science Foundation of China;Project(2021M693843)supported by the China Postdoctoral Science Foundation;Project(21RJ7RA309)supported by Natural Science Foundation of Gansu Province,China;Project(1520260306)supported by Tianyou Youth Talent Lift Program of Lanzhou Jiaotong University,China。

摘　　要：黄土隧道抗震多采用确定性分析方法。考虑地震动的随机性,采用拟静力法对黄土地层中的浅埋地铁隧道在横向地震作用下的地震易损性进行分析,施加一维分析计算的位移得到隧道的地震响应,然后通过Python程序输出最大损伤指标。采用相关性、有效性、实用性和效益性等判定准则遴选出最优地震动强度参数。根据易损性函数,建立了基于地表峰值加速度(PGA)和地表峰值速度(PGV)的易损性曲线以评估隧道的抗震性能。结果表明:不同PGA条件下隧道衬砌的易损部位沿共轭45°方向发生偏转;PGA和PGV是预测隧道在不同损伤状态下损伤概率的合适强度参数;隧道拱顶空洞会增大隧道的地震易损性;处于较软工程场地的隧道更容易遭受地震破坏。The deterministic method is always adopted for the seismic resistance of loess tunnels.Considering the randomness of ground motions,the seismic fragility assessment of a shallowly buried circular tunnel in the loess region was carried out under pseudo-static conditions with seismic loading in the transversal direction.The displacements calculated by one-dimensional analysis were applied to obtain the seismic responses of the tunnel.Then the maximum damage index was output by a compiled Python program.The optimality of intensity measures was briefly discussed through the testing criteria of correlation,efficiency,practicality,and proficiency.Fragility curves were generated based on the fragility function in terms of peak ground acceleration(PGA)and peak ground velocity(PGV)to evaluate the tunnel's seismic performance.The results show that the vulnerable parts that shift with different PGAs in conjugate directions are particularly prone to suffering damage.And PGA and PGV are identified as the appropriate indices for predicting the probability of tunnels in various damage states.Void behind the arch dome can increase the fragility of tunnels,and the tunnels embedded in softer sites become more vulnerable to seismic damage.

关 键 词：黄土隧道 地震易损性评价 抗震性能 损伤指标 拟静力分析 

分 类 号：U231[交通运输工程—道路与铁道工程] U452.28[建筑科学—桥梁与隧道工程]