高速铁路桥梁方向脉冲型近断层地震反应分析  

Analysis of Seismic Response of Directivity Pulse-like Near-fault Ground Motion to Bridge of High-speed Railway

作　　者：陈令坤[1] 张楠[1] 蒋丽忠[2] 陈格威[3] 

机构地区：[1]北京交通大学,北京100044 [2]中南大学,长沙410075 [3]奥克兰大学

出　　处：《铁道工程学报》2013年第9期40-46,共7页Journal of Railway Engineering Society

基　　金：国家重点基础研究发展计划(973计划)资助(2013CB036203);中国博士后科学基金资助(2013M530022);住房和城乡建设部科学技术计划项目(2013-K5-31)

摘　　要：研究目的:近年来,近断层地震对桥梁响应的影响日益引起研究者的注意,现有铁路规范对近断层效应的考虑较少。为研究方向速度脉冲效应对高速铁路桥梁地震响应的影响,基于Pacific Earthquake Engineering Research Center(PEER),Next Generation Attenuation Relationships for Western US(NGA West)强震数据库,采用ANSYS分析软件、ANSYS-APDL语言和弯矩曲率关系计算程序,建立了高速铁路桥梁全桥模型,考虑了轨道不平顺的影响,计算了近/远断层地震作用下桥梁的弹塑性地震响应。研究结论:(1)相比于远断层地震以及非脉冲型地震,方向脉冲型近断层地震对短周期结构地震响应影响较大,会增加桥梁位移及内力响应,其滞回特性表现出荷载-变形曲线中间加强的特点,会增加桥梁的结构和非结构损伤;(2)由于近断层地震较大的竖向地震动会改变桥墩轴力,导致梁体竖向挠度比远断层地震增加较多,《铁路工程抗震设计规范》(GB 50111—2006)等规范规定竖向地震为横向的65%,会低估梁体竖向动力响应;(3)本文研究成果可以为高速铁路桥梁抗震设计提供参考,也为今后相关设计规范、标准的修订提供技术支持。Research purposes： Recently, the more attentions have been paid to the influence of the near- fault ground motion on the dynamic response to bridge, but there is a little concerns about the near -fault ground motion effect in the current railway codes. To investigate the influence of the seismic response of the near - fault ground motion on high - speed railway bridge, by using the Pacific Earthquake Engineering Research Center （PEER）, the Next Generation Attenuation Relationships for Western US （ NGA West ） strong ground motion database, the ANSYS software, the ANSYS - APDL language and the moment - curvature program, the finite element model for the multi - span simply - supported bridge of the high - speed railway was built on consideration of the influence of the track irregularity to calculate the elastic - plastic seismic responses of bridge subjected to the near/far - fault ground motions. Research conclusions： （ 1 ） Compared with far - fault ground motion and non - pulse - like motion, the directivity pulse - like Near- fault ground motion had a big influence on the seismic responses on the short -period structure, increased the displacement response of inelastic bridge structures and it also increased the structural and nonstructural damage because the hysteretic properties of the near- fault directivity pulse -type earthquake was characterized by the central strengthened hysteretic cycles. （2） The big vertical acceleration of near - fault directivity pulse - like motion could notably change the axial load of the bridge piers, resulting in big increase of vertical deflection in the mid - span of girder, but the vertical earthquake force is specified as 65 % of the lateral earthquake in the （（ Code for Seismic Design of Railway Engineering））（ GB 50111 -2006 ） and it causes the smaller vertical deflection in the girder. （3） The calculation results could technical support for the provide the reference to the seismic design of high - speed railway bridge, and provide the r

关 键 词：NGA West强震库 方向脉冲效应 近断层地震 高速铁路桥梁 弹塑性响应 

分 类 号：U448.13[建筑科学—桥梁与隧道工程]