行波激励对非对称矮塔斜拉桥抗震性能的影响  

Seismic behavior of asymmetric extradosed bridge with action of traveling wave effect

作　　者：潘思璇 唐冕[1] 宋旭明[1] PAN Sixuan;TANG Mian;SONG Xuming(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2020年第7期1862-1872,共11页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51178471,51508574)。

摘　　要：为研究非对称结构矮塔斜拉桥的抗震性能,基于实际工程案例,采用Midas Civil软件建立非对称矮塔斜拉桥有限元模型,并根据大质量法理论模拟行波激励,分析地震动的内力与位移响应,结合能量法计算滞回耗能和损伤系数,研究行波效应对近波源桥塔及延性抗震的影响。研究结果表明:非对称矮塔斜拉桥在不同向地震作用下中墩内力响应最为显著;行波效应会削弱边塔底部的抗弯、剪承载能力,不同行波激励均对中塔顶顺桥向位移有较大影响。结合受力规律提出非对称结构在抗震设计时只考虑一致激励将造成中墩安全隐患,且随着桥跨不对称性增大设计时应着重考虑边墩受力。In order to explore the anti-seismic performance of extradosed bridges designed with asymmetrical structures, Midas Civil software was used to establish a finite element model of asymmetrical extradosed bridge based on an actual bridge construction. Traveling wave effect was simulated relying on large-mass method(LMM),and the internal force and displacement response to ground motion were analyzed. Combined with the energy method to calculate hysteretic energy consumption and damage coefficient, the influence of traveling wave effect on the near-wave source bridge tower and ductile earthquake resistance was studied. The results show that the asymmetrical extradosed bridge has the most significant response to the internal force of the middle pier during different earthquakes;the traveling wave effect will weaken the bend and shear bearing capacity of the bottom of the side tower, and different traveling wave excitations have a great influence on the displacement of the middle tower along the bridge. Combined with the law of stress, the hidden danger of the middle pier will be caused during anti-earthquake design if only the consistent excitation is consiclered, as the asymmetry of the bridge span increases, and the stress on the side pier should be considered.

关 键 词：矮塔斜拉桥 非对称结构 大质量法(LMM) 行波效应 滞回耗能 损伤系数 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]