地震动行波效应对连续梁桥纵向地震碰撞反应的影响  

SEISMIC WAVE PASSAGE EFFECT'S INFLUENCES ON LONGITUDINAL SEISMIC POUNDING RESPONSE FOR CONTINUOUS GIRDER BRIDGES

作　　者：王军文[1] 张运波[1] 李建中[2] 范立础[2] 

机构地区：[1]石家庄铁道学院土木工程分院,石家庄050043 [2]同济大学桥梁工程系,上海200092

出　　处：《工程力学》2007年第11期100-105,共6页Engineering Mechanics

基　　金：国家自然科学基金资助项目(50578118);河北省教育厅科研计划资助项目

摘　　要：在等墩高的多跨连续梁桥中,虽然相邻联的基本振动周期完全相同,地震动的行波效应可能导致伸缩缝处相邻梁体间发生碰撞。采用接触单元模拟伸缩缝处相邻梁体间的碰撞,采用阻尼器来反映碰撞过程中的能量损失,应用非线性时程方法研究了地震动行波效应对连续梁桥纵向地震碰撞反应的影响。研究结果表明:地震动的行波效应在伸缩缝处相邻梁体间引起较大的相对位移,导致相邻梁体间发生碰撞,碰撞力的大小随表面视波速不同而不同。行波效应引起的伸缩缝处相邻梁体间碰撞,可能增大伸缩缝处相邻梁体间以及墩梁间相对位移,甚至造成上部结构在地震中发生落梁破坏,在连续梁桥的抗震设计与评估中,应该引起足够的重视。In multiple continuous girders with piers of the same height, although natural periods of adjacent segments at expansion joints are the same, pounding between adjacent segments at expansion joints can be induced by seismic wave passage effect. In this paper, the seismic pounding responses between adjacent girder decks at expansion joints of continuous girder bridges due to seismic wave passage effect were investigated by the nonlinear time history analysis method. In analysis, contact element is used to model pounding and damper is used to describe the energy dissipation during collision. The results show that seismic wave propagation effect can cause relative displacements between adjacent bridge decks enough large to induce impact at expansion joints. The magnitude of pounding force depends on apparent velocity of seismic wave. Pounding can amplify relative displacements between adjacent bridge decks or piers and decks, which may even cause bridge decks to drop from piers and collapse. Therefore, influences of seismic wave passage effect on longitudinal seismic pounding response should be emphasized in seismic design and assessment for continuous girder bridges.

关 键 词：桥梁 地震 行波效应 碰撞 地震反应 

分 类 号：TU311.3[建筑科学—结构工程]