考虑行波效应的大跨悬索桥地震响应研究  

Research on Seismic Responses of Long-Span Suspension Bridge Considering Traveling Wave Effects

作　　者：黄月超 周强 吴鸿 黄鸿楷 李悦 HUANG Yuechao;ZHOU Qiang;WU Hong;HUANG Hongkai;LI Yue(CCCC Highway Consultants Co.,Ltd.,Beijing 100010,China;Guangxi Xingang Transportation Investment Co.,Ltd.,Nanning 530022,China;School of Civil Engineering,North China University of Technology,Beijing 100144,China)

机构地区：[1]中交公路规划设计院有限公司,北京100010 [2]广西欣港交通投资有限公司,广西南宁530022 [3]北方工业大学土木工程学院,北京100144

出　　处：《世界桥梁》2025年第1期64-70,共7页World Bridges

基　　金：国家自然科学基金项目(51408009);北方工业大学国家级项目支撑专项项目(1100513623XN-283-28)。

摘　　要：为给设置外伸跨的大跨悬索桥抗震设计提供参考,以主跨1098 m的广西龙门大桥为背景,研究考虑行波效应对设置外伸跨大跨悬索桥地震响应的影响。建立桥梁有限元模型,获得桥梁的动力特性,计算不同视波速(1~10 km/s)地震作用下,考虑行波效应时加劲梁、桥塔及外伸跨过渡墩的动力响应与一致激励作用下的结构动力响应之比(行波效应系数)。结果表明:不同视波速下加劲梁端部位移的行波效应系数为0.85~1.10;桥塔塔底内力的行波效应系数为0.73~1.21,当视波速大于5 km/s时,行波效应与一致激励作用下桥塔塔底内力的地震响应趋向一致,且行波效应会使桥塔塔身局部剪力和弯矩突增;行波效应对外伸跨过渡墩内力的影响较小。在对设置外伸跨的大跨悬索桥进行抗震设计时,应充分考虑行波效应的影响。This study investigates the traveling wave effects on the seismic responses of the Longmen Bridge in Guangxi Province,which is a suspension bridge with a main span of 1098 m.Different from the conventional configuration,the stiffening girder consisting of steel boxes stretching 50 m out of each tower to be supported on the transition pier on each side,making the length of the steel box girder reach 1198 m,in this case,the expansion joints are set over the transition piers,and the bearings are also installed at the transition piers,instead of the cross-beam of the towers.Finite element modeling was conducted to examine the dynamic property of the bridge,calculate the dynamic responses of the stiffening girder,towers and transition piers under seismic actions at different apparent wave velocities(1 to 10 km/s),considering the traveling wave effects,which was in turn compared with the dynamic responses of the bridge under uniform excitation(traveling wave effect coefficient).It is shown that the traveling wave effect coefficients of the girder-end displacements at different apparent wave velocities are between 0.85 and 1.10,and the traveling wave coefficients of the internal forces at the pylon bottom are between 0.73 and 1.21.When the apparent wave velocity is above 5 km/s,the seismic responses of the internal forces at the pylon bottom under the traveling wave effects tend to be in line with the seismic responses under uniform excitation,and traveling wave effects would induce abrupt increase of localized shear forces and bending moments in the pylons.Traveling wave effects induce minor variation of internal forces in the transition piers.Traveling wave effects should be given enough concern in the design of similar type of suspension bridge.

关 键 词：悬索桥 加劲梁外伸跨 过渡墩 行波效应 视波速 地震响应 有限元法 

分 类 号：U448.25[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]