强震区浅埋隧道洞口段改进整体式反应位移法  

Improved Integral Response Displacement Method for Shallow-buried Tunnel Portal Section in Highly Seismic Regions

作　　者：申玉生[1,2] 赵何霖 朱正超 易鹏豪 雷龙 粟威[3] SHEN Yusheng;ZHAO Helin;ZHU Zhengchao;YI Penghao;LEI Long;SU Wei(Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031;National Engineering Research Center of Geological Disaster Prevention Technology in Land Transportation,Southwest Jiaotong University,Chengdu 610031;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031)

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610031 [2]西南交通大学陆地交通地质灾害防治技术国家工程研究中心,成都610031 [3]中铁二院工程集团有限责任公司,成都610031

出　　处：《现代隧道技术》2023年第5期78-87,共10页Modern Tunnelling Technology

基　　金：国家自然科学基金项目(52278414);国家重点研发计划(2019YFC0605104)。

摘　　要：为提高强震作用下隧道洞口段结构抗震性能,依托高烈度地震区某管道隧道工程,研究采用整体式反应位移法进行隧道洞口段抗震计算时的误差影响因素,引入结构位移放大系数,提出一种适用于隧道洞口段结构抗震计算的改进整体式反应位移法,并结合算例分析,对改进后计算方法进行验证。结果表明:采用整体式反应位移法进行隧道洞口段抗震计算时误差主要是由洞口段隧道顶底部的相对位移引起,可引入结构位移放大系数对其进行修正;结构位移放大系数与洞口仰坡坡角和地震动强度正相关,与坡高和相对埋深负相关,不同围岩级别中的放大系数偏差小于10%,可忽略围岩条件对其的影响;改进整体式反应位移法在0.6g地震动下误差基本小于10%,比整体式反应位移法精度更高,可应用于隧道洞口段的抗震计算。In order to improve the seismic performance of the tunnel portal structure under strong earthquakes,based on a pipeline tunnel project in a high-intensity seismic area,the error influencing factors of the integral re⁃sponse displacement method in seismic calculation of the tunnel portal section are studied.The structural displace⁃ment amplification coefficient is introduced,and an improved integral response displacement method suitable for structural seismic calculation of the tunnel portal is proposed.Furthermore,the improved calculation method is veri⁃fied based on case analysis.The results show that the error in the seismic calculation of the tunnel portal section using the integral response displacement method is mainly caused by the relative displacement between the top and the bottom of the tunnel at the tunnel portal section,and it can be corrected by introducing a structural displacement am⁃plification coefficient.The structural displacement amplification coefficient is positively correlated with the front slope angle of the tunnel portal and the seismic intensity,but negatively correlated with the slope height and relative burial depth.The deviation of amplification coefficient in different levels of surrounding rock is less than 10%,and the influence of surrounding rock conditions on it can be ignored.The error of the improved integral response dis⁃placement method under 0.6g seismic motion is basically less than 10%,which has higher accuracy than the inte⁃gral response displacement method and can be applied to seismic calculation of the tunnel portal section.

关 键 词：隧道工程 抗震设计 位移放大系数 改进整体式反应位移法 

分 类 号：U458[建筑科学—桥梁与隧道工程]