分梁共墩式公轨合建双层高架桥的抗震分析  

Seismic analysis of an integrated double-deck viaduct with splited beams and shared piers

作　　者：陈智钊 刘周强 徐艳[1] 梁博 CHEN Zhizhao;LIU Zhouqiang;XU Yan;LIANG Bo(State Key Laboratory for Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China;Jianfa Real Estate Group,Shanghai 200092,China;Shanxi Road&Bridge Construction Group Co.,Ltd.,Taiyuan 030006,China)

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092 [2]建发房地产集团上海有限公司,上海200092 [3]山西路桥建设集团有限公司,太原030006

出　　处：《振动与冲击》2023年第8期79-86,共8页Journal of Vibration and Shock

摘　　要：公轨合建双层高架可将城市高架和轨道交通线路组合起来,节省城市用地的同时便于疏散交通压力,在近年来的城市交通规划中得到重视和应用。但由于缺少专门的抗震设计规范,此类桥梁的抗震设防标准、性能目标和抗震设计方法亟需研究。该研究以一座实际桥梁为背景工程,提出合理的抗震设防标准和性能目标,研究轨道对结构动力特性和弹性地震响应的影响,并进一步采用非线性纤维模型研究桥墩纵筋配筋率、墩梁刚度比以及上、下墩高比对桥墩屈服顺序的影响。研究表明,轨道增大了结构纵向刚度和下桥墩与下盖梁的地震响应,分梁共墩式双层高架宜采用延性抗震设计,将盖梁设计为能力保护构件,并通过合理的墩梁截面刚度、墩高和配筋率设计满足两水准的性能目标,确保地震作用下结构产生预期的延性破坏模式。An integrated viaduct can accommodate an urban viaduct with rail transit lines,saving construction space and helping relief traffic pressure,and thus has received increasing attention and applications in urban transportation planning in recent years.However,due to the lack of speciallized seismic design specifications,the seismic fortification standards,performance objectives and seismic design methods of such bridges need to be studied urgently.Taking an actual bridge as the background project,reasonable seismic fortification standards and performance objectives were proposed,and the influence of the track on the dynamic characteristics and elastic seismic response of the structure was then studied.The nonlinear fiber model was further adopted to study the influence of pier longitudinal reinforcement ratio,pier-beam stiffness ratio,and height ratio of upper and lower piers on the pier’s yielding sequence.The research shows that the track increases the longitudinal stiffness of the structure and the seismic response of the lower pier and the cap beam,and the ductile seismic design should be adopted for the integrated viaduct,the cap beam should be designed as a capacity protected member,and the two-level performance objectives should be satisfied through reasonable design of pier-beam section stiffness,pier height and reinforcement ratio,ensuring that the structure produces an expected ductile failure mode subjected to earthquake shaking.

关 键 词：公轨合建 双层高架 分梁共墩 轨道 抗震设计 

分 类 号：U448.28[建筑科学—桥梁与隧道工程] U442.55[交通运输工程—道路与铁道工程]