摘要
针对隧道洞身段衬砌拱顶结构背后出现空洞的情况,开展大型振动台隧道模型试验研究,主要通过加速度响应特征、应变响应特征和震后衬砌破坏形态,探究竖向地震动作用下衬砌拱顶背后空洞对隧道衬砌动力响应的影响。同时结合傅里叶谱和频率传递函数方法,从频域角度展示衬砌结构频谱特性的变化。研究结果表明:无论衬砌背后有、无空洞,竖向地震动都对衬砌结构的拱顶、拱脚和仰拱影响较大;空洞并不改变隧道洞身的加速度响应特征,只改变了加速度响应峰值,空洞处衬砌加速度峰值大于密实段加速度峰值;输入地震动峰值越大,空洞对衬砌结构的加速度响应影响越显著;空洞并不改变结构响应的频谱特性,地震作用下衬砌结构的自身的主频成分被激发,衬砌位置的一阶频率和二阶频率分别反映模型土的动力特性和衬砌结构的动力特性;在强震作用下,拱顶空洞的存在改变了衬砌结构拱顶和拱脚的受力状态,密实段衬砌拱顶和仰拱处出现较大拉应变,而拱脚出现较大压应变;空洞处衬砌拱顶、拱脚和仰拱均出现较大拉应变。
A large shaking table model test was carried out to investigate the dynamic response of the tunnel lining with a void behind the crown, and the test results were discussed based on the acceleration response characteristics,strain response characteristics and damage patterns of the tunnel lining under vertical ground motions. Combining with the Fourier spectrum and the frequency transfer function,the spectrum characteristics of the lining structure were demonstrated. The results show that the vertical ground motion mainly affects the crown,arch springing and invert of the lining with or without voids. The voids increase the peak value of the acceleration response of the tunnel while have no influence on the characteristic of the acceleration response. The larger the input peak ground motion is,the more significant the effect of voids on the acceleration response of the lining structure is. The existence of voids does not change the spectral characteristics of the structural response. The main frequency component of the lining structure is excited under earthquake action,and the 1 st and 2 nd dominant frequencies at the lining reflect the seismic properties of model soil and lining structure respectively. The void behind the crown changes the stress states of the crown and arch springing of the lining. For the lining without voids,large tension strains appear at the crown and invert while large compression strains occur at the arch springing. In the case of the lining with voids,however,large tension strains appear at the crown,arch springing and invert.
作者
闫高明
申玉生
信春雷
高波
周鹏发
张熙
杨佳奇
YAN Gaoming;SHEN Yusheng;XIN Chunlei;GAO Bo;ZHOU Pengfa;ZHANG Xi;YANG Jiaqi(Kwy Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu,Sichuan 610031,China;College of Environment and Civil Engineering,Chengdu University of Technology^Chengdu,Sichuan 610059,China;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology Chengdu,Sichuan 610059,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2019年第12期2491-2501,共11页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51678501,51778540)
“十三五”国家重点研发计划(2016YFB1200401)~~
关键词
隧道工程
动力响应
频率传递函数
空洞
振动台模型试验
tunnel engineering
dynamic responses
frequency transfer functions
void
shaking table tests
