大跨超长联跨海连续梁桥纵向抗震体系研究  

Research of longitudinal seismic system for long-span and super-long unit continuous girder bridge crossing the sea

作　　者：张景钰 何友娣[1] 李龙安[1] Zhang Jing-yu;He You-di;Li Long-an(China Railway Major Bridge Reconnaissance&Design Institute Co.Ltd,Wuhan 430056,China)

机构地区：[1]中铁大桥勘测设计院集团有限公司,湖北武汉430056

出　　处：《工程抗震与加固改造》2024年第4期41-49,共9页Earthquake Resistant Engineering and Retrofitting

基　　金：青年人才托举工程(2021QNRC001)。

摘　　要：为研究大跨超长联跨海连续梁桥的纵向抗震体系,以某长联连续梁桥[(60+22×80+60)m]为研究对象,采用传统隔震体系和减隔震体系进行抗震设计,采用Midas/Civil建立全桥有限元模型,比较采用不同抗震体系及其边界参数时桥墩在罕遇地震作用下的地震响应。计算结果表明:对于传统体系,设置多个固定墩,可以在一定程度上降低结构的内力响应和限制桥梁的纵向位移,但结构内力和位移仍处于较高的水平,因此设置多个固定墩并不是行之有效的抗震结构体系;对于延性设计,塑性铰的耗能特性可以有效降低结构内力响应,其塑性变形特性会增大位移响应,但对于位于水中的桥墩,鉴于震后构件修复的难易程度,当考虑采用延性设计体系时应当予以更多的关注;对于减隔震体系,摩擦摆支座可以有效降低结构内力和限制桥梁的纵向位移,具有良好的减隔震效果,结构的安全性得到了显著提高,结构内力和位移与减隔震支座的个数之间并非简单的线性关系,应通过对结构内力的详细计算后确定。To investigate the longitudinal seismic system of long-span and super-long continuous bridge across the sea,a continuous girder bridge with span arrangement(60+22×80+60)m was cited as an example and the seismic design of the bridge was carried out,respectively using the conventional seismic system and the seismic mitigation and isolation system.The software Midas/Civil was used to set up the finite element model for the overall bridge model.And the responses of the piers of the bridge using different seismic systems with different boundary parameters under the action of the rare earthquake were compared.The results show that when the conventional seismic system is used on the bridge with multiple fixed piers,it can reduce the internal force response of the piers and limit the longitudinal displacement of the bridge to a certain extent,but the internal forces and displacement of the bridge are still at a high level.Therefore,conventional seismic system is not an effective seismic system.For the ductility seismic system,the energy dissipation effect of plastic hinge can effectively reduce the internal force response of piers,and its plastic deformation effect will increase the longitudinal displacement of the bridge.However,for bridge piers located in water,due to the difficulty of repairing components after earthquakes,more attention should be paid when considering the use of a ductile design system.When the seismic mitigation and isolation system is used on the bridge,friction pendulum bearings can effectively reduce the internal forces of piers and limit the longitudinal displacement of the bridge which have excellent effect of seismic isolation.Friction pendulum bearings also significantly improve the safety of the bridge.The relationship between the response internal force and displacement of the bridge and the number of isolation bearings do not obey linear relationship,which should be determined after detailed calculation.

关 键 词：大跨超长联 抗震体系 传统设计 减隔震设计 延性设计 抗震性能 连续梁桥 

分 类 号：U448.215[建筑科学—桥梁与隧道工程]