多维地震作用下高铁桥梁圆端形桥墩易损性分析  

Fragility Analysis of the Round-ended Pier of High-speed Railway Bridges Subjected to Multi-dimensional Ground Motions

作　　者：沈惠军 王浩[1] 郑文智 梁瑞军 沙奔 许俊红 SHEN Huijun;WANG Hao;ZHENG Wenzhi;LIANG Ruijun;SHA Ben;XU Junhong(Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education,Southeast University,Nanjing 210096,Jiangsu,China;Second Harbour Engineering Co.,Ltd.,China Communications Construction Company Ltd.,Wuhan 430040,Hubei,China;Key Laboratory for Construction Technology of Long Span Bridges,Ministry of Transport,Wuhan 430040,Hubei,China;College of Civil Engineering,Nanjing Forestry University,Nanjing 210037,Jiangsu,China)

机构地区：[1]东南大学混凝土及预应力混凝土结构教育部重点实验室,江苏南京210096 [2]中交第二航务工程局有限公司,湖北武汉430040 [3]长大桥梁建设施工技术交通行业重点实验室,湖北武汉430040 [4]南京林业大学土木工程学院,江苏南京210037

出　　处：《地震研究》2021年第2期225-232,共8页Journal of Seismological Research

基　　金：国家自然科学基金项目(51578151);国家“万人计划”青年拔尖人才(W03070080);江苏省重点研发计划项目(BE2018120);江苏省自然科学基金(BK20180776);江苏省高校自然科学基金(18KJB560013);住房和城乡建设厅科学技术项目(2018-K9-068)联合资助。

摘　　要：圆端形桥墩在高铁桥梁中应用广泛,为研究其在多维地震动作用下的易损性,首先基于OpenSees建立了某典型三跨高铁连续梁桥的非线性动力分析模型;然后以相对位移延性比为桥墩的损伤指标,确定了固定中墩各破坏状态的相对位移延性比界限值;最后,在考虑地震动输入角的基础上,基于易损性分析方法,对比分析了固定中墩顺桥向和横桥向的地震响应。结果表明:①同一地震动输入角下,固定中墩顺桥向的墩顶峰值位移平均值远大于横桥向;②当PGA值和地震动输入角都相同时,固定中墩顺桥向达到各破坏状态的概率明显大于横桥向,因此,在设计时应优先考虑顺桥向的破坏概率;③固定中墩顺桥向各破坏状态易损性云图的波动性明显大于横桥向,所以地震动输入角对固定中墩顺桥向的影响不容忽视。The round-ended pier is widely used for high-speed railway bridges.In order to study its fragility subjected to multi-dimensional ground motions, the finite element model of a typical three-span, continuous girder bridge of the high-speed railway is performed based on OpenSees.Then, the relative displacement ductility ratio of the pier is defined as the damage index, and its limit values for the damage state of each fixed pier are determined.Finally, in the case of different angles of input ground motions, seismic responses of the fixed middle pier along the longitudinal and the transverse directions are compared based on the vulnerability analysis method.Results show that:① The average peak displacement the fixed middle pier along the longitudinal direction is much larger than that along of the transverse direction on condition of the same input angle;② On condition of the same PGA and input angle, the failure probability of the fixed middle pier along the longitudinal direction is significantly higher than that along the transverse direction.Therefore, the failure probability along the longitudinal direction should be given priority in pier designing;③ The fluctuation of the contour plots for the fragility of the fixed middle pier along the longitudinal direction in different damage states is obviously higher than that along the transverse direction.Hence the effect of the input angle of the ground motion on the fixed middle pier should be a matter of concern.

关 键 词：高铁桥梁 圆端形桥墩 地震易损性 多维地震动 相对位移延性比 地震动输入角 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]