海底盾构隧道-竖井连接部位三维非线性地震反应特性  

3D nonlinear seismic response characteristics for the junction of undersea shield tunnel-shaft

作　　者：陈国兴[1,2] 卢艺静 王彦臻 阮滨 CHEN Guo-xing;LU Yi-jing;WANG Yan-zhen;RUAN Bin(Institute of Geotechnical Engineering,Nanjing Tech University,Nanjing 210009,China;Civil Engineering and Earthquake Disaster Prevention Center of Jiangsu Province,Nanjing 210009,China;School of Civil Engineering and Mechanics,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]南京工业大学岩土工程研究所,江苏南京210009 [2]江苏省土木工程防震技术研究中心,江苏南京210009 [3]华中科技大学土木工程与力学学院,湖北武汉430074

出　　处：《岩土工程学报》2021年第8期1382-1390,I0004,I0005,共11页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51438004)。

摘　　要：海底盾构隧道-竖井连接部位在地震作用下易发生损坏。以汕头海湾海底隧道为例,考虑海床土体和混凝土的非线性,利用多点约束与连接单元模拟管环间的螺栓连接,经幅值标定的不同特性的强震记录作为输入基岩地震动,采用动力时程法(纵轴向+横向+竖向震动、纵轴向+竖向震动)与广义反应位移法(纵轴向+横向+竖向震动)对比分析了盾构隧道-竖井连接部位的三维非线性地震反应特性。不同特性的地震动作用下,多点约束与连接单元能有效模拟盾构隧道管环间的变形特性,管环拱顶与外拱肩处的张开量较大;竖井在与竖轴共轭45°方向上的损伤严重、应力集中显著;低频丰富的地震记录激励比高频发育的地震记录激励对该连接部位的影响更大。隧道-竖井接头处的地震变形与应力远大于距离接头较远处隧道管环的地震变形与应力,且横向地震激励的影响不容忽视。两种方法计算的连接部位沿隧道纵向的地震反应特征一致,但广义反应位移法计算的隧道、竖井的地震反应明显大于动力时程法的结果。The junction of the subsea shield tunnel-shaft is prone to damage subjected to strong earthquakes.Taking the subsea shield tunnel crossing under the Shantou Gulf,China as a case study,the three-dimensional seismic response characteristics of the junction of the subsea shield tunnel-shaft are analyzed using the dynamic time-history analysis method(longitudinal axial+transverse+vertical shakings,longitudinal axil+vertical shakings)and the generalized response displacement method(longitudinal axial+transverse+vertical shakings),which considers the nonlinear dynamic behaviors of the seabed soil and concrete,the simulation of the bolt joints between ring segments by using multi-point constraints and connection elements as well as the ground motions produced by scaling from the strong earthquake records.The results show that under all the input bedrock motions with various characteristics,the deformation features between segment rings can be simulated effectively by the multi-point constraints and connection elements,and the opening widths between ring segments at the ring top and outside spandrel are larger.Serious seismic damage and stress concentration exist at the conjugate with direction of 45°of shaft.The seismic responses of the tunnel-shaft junction subjected to the earthquake motions with rich low frequency components are much stronger than those of earthquake motions with rich high ones.The seismic deformation and stress of the tunnel-shaft junction are much greater than those of the ring segments,and the influences of the horizontal shaking along the transverse direction of the tunnel on the seismic responses of the ring segments and the tunnel-shaft junction cannot be ignored.The spatial variation of the seismic responses of the ring segments along the tunnel longitudinal axis and the tunnel-shaft junction calculated by the two methods is consistent,whereas the seismic responses calculated by the generalized response displacement method are much larger than those calculated by the dynamic time-history anal

关 键 词：隧道-竖井连接部位 动力时程法 广义反应位移法 管环间张开量 地震损伤 

分 类 号：TU43[建筑科学—岩土工程]