摘要
以均质地层长隧道结构为对象,将长隧道简化为作用在均匀地层中的弹性地基梁,采用法向和切向地基弹簧模拟地层与结构相互作用,建立相应的微分控制方程,推导出均质地层长隧道纵向地震响应的解析表达式。通过对隧道结构内力响应解析解的分析,提出面向长隧道纵向抗震设计所需最大内力响应解(弯矩、剪力、轴力)的计算方法,可用于快速计算均质地层长隧道纵向最不利地震响应。将解析解与有限元模拟结果进行对比分析,结果表明解析解与数值解基本一致,验证了本研究解析解的正确性。该解析解可以直观地给出各关键参数之间的解析关系,通过参数敏感性分析,得出了地震波不同入射角度、入射波长和地层-结构相对刚度比等关键因素对隧道纵向地震响应的影响规律。分析表明:随着地震波入射波长变长,隧道弯矩响应先增大后减小,而剪力和轴力响应均减小;随着地震波入射角从0°增加到90°,隧道剪力响应变小,弯矩和轴力响应先增大后减小;随着地层-结构相对刚度比变大,隧道内力响应均出现一定程度降低,且弯矩、轴力响应呈现明显降低趋势,但隧道位移响应随相对刚度比变大,隧道沿纵向出现较大的变形,结构设计应该综合考虑内力和变形两方面因素。在此基础上提出了长隧道纵向地震响应解析的合理设计计算方法,可为今后隧道纵向抗震设计提供指导。
Long tunnel in homogeneous stratum was studied,which was simplified to a beam on elastic foundation.Soil-structure interaction was simulated by normal and tangential spring.Analytical solution of longitudinal seismic response was derived by solving governing differential equations.Through the analysis of the analytical solution of the internal force response,the calculation method of the maximum internal force response required for the longitudinal seismic design was put forward,which could be used to calculate the most unfavorable longitudinal response of long tunnel.On the basis of numerical calculation,the correctness of the analytical solution was verified.In addition,the analytical solution could intuitively give the correlations among the key parameters.Through parametric analysis,influence laws of incident angle,incident wavelength and relative stiffness ratio on longitudinal seismic response of tunnels were obtained.Analysis showed that as the wavelength of incident wave increased,the bending moment response first increased and then decreased,and the shear force and axial force response decreased.If the incident angle increased from 0°to 90°,the shear response decreased,while the bending moment and axial force first increased and then decreased.As the relative stiffness ratio increased,internal force response was reduced,but the displacement response of the structure and the deformation of tunnel structure would appear larger,which should be considered in the structural design.On this basis,a reasonable design and calculation method of longitudinal seismic response analysis of long tunnels was put forward,which could provide guidance for longitudinal seismic design of long tunnels.
作者
禹海涛
王祺
刘涛
YU Haitao;WANG Qi;LIU Tao(Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education,Tongji University,Shanghai 200092,China;Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China;Shanghai Huangpu River Crossing Facility Investment Construction Development Co.,Ltd.,Shanghai 200335,China)
出处
《隧道与地下工程灾害防治》
2020年第1期34-41,共8页
Hazard Control in Tunnelling and Underground Engineering
基金
国家自然科学基金资助项目(41922059&51678438)
国家重点研发计划资助项目(2018YFC1504305&2018YFC0809602&2017YFC1500703)
中央高校基本科研业务费专项资金资助项目
上海市科委重点课题资助项目(18DZ1205103&17DZ1203804&17DZ1203402)
关键词
地下结构
地震响应
抗震设计
解析解
地层-结构相对刚度比
underground structure
seismic response
seismic design
analytical solution
soil-structure relative stiffness
作者简介
禹海涛(1983—),男,河南泌阳人,教授,工学博士,博士后,博士生导师,主要研究方向为地下结构抗震与抗爆动力学.E-mail:yuhaitao@tongji.edu.cn
