行波效应对大跨多塔悬索桥纵向约束体系影响研究  

Effect of Seismic Wave Propagation on the Constraint Systems of a Long-span Multi-tower Suspension Bridge

作　　者：闫聚考[1] 李建中[1] 彭天波[1] 

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

出　　处：《结构工程师》2014年第4期46-51,共6页Structural Engineers

基　　金：国家科技支撑计划资助项目(2009BAG15B01);国家重点基础研究发展计划(2013CB036302)

摘　　要：大跨度多塔悬索桥各地面支承距离很大,行波效应对结构地震反应影响较大。基于直接输入位移法建立了多点激励时程分析模型。选取一座全长2 940 m的三塔两跨悬索桥为研究对象,分析了不同的塔梁纵向约束体系以及不同视波速下行波效应对大跨多塔悬索桥的影响。研究结果表明:行波效应可能会增大边塔底部的内力而减小中塔底部的内力,行波效应也可能会增大塔梁的相对位移和主梁与引桥梁的相对位移。因此,在对大跨度多塔连跨悬索结构进行抗震分析时,必须考虑行波效应的影响。For long-span multi-tower suspension bridges,the wave propagation effect has great impacts on structural seismic responses.A time history analytical model under multi-support excitations was established based on the direct displacement input method.A 2940-m three-tower two-span suspension bridge was selected for study.Nonlinear time-history analyses were performed and the influence of wave propagation on the long-span multi-tower suspension bridge was discussed in terms of different longitudinal constraint systems and wave traveling velocities.The results indicate that wave-traveling effect can increase the force in side towers but re-duce the force of the middle tower.It can also increase the relative displacement of tower-beam and the dis-placement between the main beam and the approach bridge beam.Therefore,the wave propagating effect should be considered in the seismic analysis of long-span multi-tower suspension bridges.

关 键 词：三塔两跨悬索桥 行波效应 约束体系 绝对位移法 

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]