穿越断层分段柔性接头隧道纵向地震响应解析解  

Analytical solution to longitudinal seismic response of fault-crossing tunnel with segmented flexible joints

作　　者：闫高明 赵伯明[1,2] 高波[3] 王子珺[1,2] YAN Gaoming;ZHAO Boming;GAO Bo;WANG Zijun(Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]北京交通大学城市地下工程教育部重点实验室,北京100044 [2]北京交通大学土木建筑工程学院,北京100044 [3]西南交通大学交通隧道工程教育部重点实验室土木工程学院,成都610031

出　　处：《振动与冲击》2022年第13期228-238,共11页Journal of Vibration and Shock

基　　金：中央高校基本科研业务费专项资金资助(2021JBM038);国家自然科学基金项目资助(51778046,51808035)。

摘　　要：隧道穿越活动断层段是地震中破坏最为严重的区域之一,是隧道抗减震设计的关键控制区域。对于穿越断层隧道,设置柔性接头是一种有效的抗减震措施。针对穿越断层隧道柔性接头无可用抗震设计方法的现状,基于隧道的灾变特性和柔性接头的设计理念,提出柔性接头力学模型,建立了面向工程设计的穿越断层分段柔性接头隧道纵向抗震简化分析方法。然后通过与有限元数值解和现有研究的对比分析,验证了该方法的有效性和可行性。最后应用该解析式进行了敏感性参数分析,揭示了结构刚度、断层宽度等关键因素对穿越断层分段柔性接头隧道地震响应的影响规律。研究结果表明:(1)柔性接头能增大衬砌的可允许变形能力,有效减小隧道衬砌的内力,使断层对隧道动力响应影响局部化。无论是否设置接头,穿越断层隧道受力的不利位置主要分布在断层中部和断层与上下盘接触面位置,是抗震设防需重点关注的区域;(2)增大衬砌的弯曲刚度会减小衬砌上的位移响应,也增大其在两接头位置的位移差,同时会显著增大衬砌上的内力响应值;(3)断层破碎带宽度的增大,隧道的位移增大,衬砌的弯矩响应最大值也增大,而剪力响应最大值表现为先增大后减小的趋势,其对隧道沿轴向地震响应的影响范围也增大。The areas where tunnels run through faults are seriously damaged in earthquakes,and they are the key areas for seismic design.For fault-crossing tunnels,the flexible joint is an effective aseismic measure.In view of the situation of no available aseismic design methods for flexible joints of tunnels through faults,a mechanical model of flexible joint is proposed based on the damage characteristics of tunnel and the design concept of flexible joint,and a simplified analysis method for longitudinal seismic responses of fault-crossing tunnels with flexible joint is established for engineering design.Then,the effectiveness and feasibility of the proposed method are verified by using contrastive analysis among its analytical solution,the finite element numerical solution and the existing research.Finally,the sensitivity analysis of parameters is carried out using the proposed method to reveal influences of parameters on seismic responses of tunnels through fault.The results show that:(1)the flexible joint can increase the allowable deformation capacity of the lining,effectively reduce the internal force of the tunnel lining,and localized the influence of fault on the dynamic responses of the tunnel;no matter whether the joint is set up or not,the disadvantageous load-bearing positions of fault-crossing tunnels are mainly distributed in the middle of fault area and the contacts between fault and hanging wall or footwall,which are the key areas of seismic fortification;(2)increasing the bending stiffness of the lining can reduce the displacement responses of the lining,increase the displacement differences of lining at the position of the two joints,and significantly increase the internal force responses on the lining as well;(3)with the increase of the fault width,the displacement and bending moment of the tunnel increase,while the maximum shear force increases first and then decreases,and the influence ranges of fault on the dynamic response of the tunnel along the axial direction increase.

关 键 词：隧道工程 柔性接头 纵向地震响应 解析方法 断层 

分 类 号：U451.4[建筑科学—桥梁与隧道工程]