考虑入射角影响的H型超高墩连续刚构桥地震易损性研究  

Seismic vulnerability of H-type ultra-high pier continuous rigid frame bridge considering effects of incident angle

作　　者：陈士通[1,2,3] 范鑫 甘平平 郭超群 向敏 CHEN Shitong;FAN Xin;GAN Pingping;GUO Chaoqun;XIANG Min(Collaborative Innovation Center for Performance and Security of Large-scale Infrastructure,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Hebei Engineering Innovation Center for Traffic Emergency and Guarantee,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China)

机构地区：[1]石家庄铁道大学大型基础设施性能与安全省部共建协同创新中心,石家庄050043 [2]石家庄铁道大学河北省交通应急保障工程技术创新中心,石家庄050043 [3]石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室,石家庄050043 [4]石家庄铁道大学土木工程学院,石家庄050043

出　　处：《振动与冲击》2025年第5期230-242,313,共14页Journal of Vibration and Shock

基　　金：国家重点研发计划课题(2021YFB2600605,2021YFB2600600);国家自然科学基金(51678376)。

摘　　要：相比常规桥梁,H型双柱式超高墩连续刚构桥梁受力更加复杂、高阶振型影响显著、纵横向刚度差异大,地震动入射角是影响其地震响应的关键因素之一,为探究入射角对其易损性的影响,以西部山区某高速铁路三跨超高墩连续刚构桥为研究对象,建立仿真模型开展地震响应分析。基于纵桥向和横桥向开展构件双向易损性分析,同时考虑超高墩、支座对桥梁系统的贡献率,基于一阶可靠度理论构建桥梁复合系统易损性模型,建立桥梁系统易损性曲面,探讨地震动入射角对桥梁系统地震易损性的影响规律。结果表明:纵向地震激励下超高墩相比中、低墩墩身中部损伤概率明显提升,且横桥向峰值曲率与能力需求比不同步,仅凭峰值曲率判断超高墩薄弱部位不能合理评估其抗震性能;墩底部位最不利入射角区间为0°~15°和165°~180°,墩身横系梁部位最不利区间为60°~120°,墩顶部位最不利区间在不同地震动强度下存在变化;支座地震易损性对地震动强度和入射角的变化较为敏感,不同工况地震激励下呈现出不同的损伤趋势且相比桥墩更易出现损伤,设计时应注重横向挡块的力学性能;桥梁系统地震易损性与地震动入射角表现出较强的相关性,最不利入射角区间为75°~105°和255°~285°。Compared with conventional bridges,H-type double-column ultra-high pier continuous rigid frame bridges are subjected to more complex forces,significantly influenced by high-order vibration modes and have large difference between longitudinal stiffness and transverse stiffness.Seismic incident angle is one of key factors affecting their seismic responses.Here,to explore effects of incident angle on their vulnerability,taking a certain high-speed railway 3-span ultra-high pier continuous rigid frame bridge in the western mountainous area as the study object,a simulation model was established to perform seismic response analysis.Based on longitudinal and transverse bridge directions,a bidirectional vulnerability analysis of components was performed considering contribution rates of ultra-high piers and supports to the bridge system.A vulnerability model of the bridge composite system was constructed based on the first-order reliability theory,and a vulnerability curved surface of the bridge system was established to explore effects of seismic incident angle on the seismic vulnerability of the bridge system.The results showed that under longitudinal seismic excitation,the probability of damage to ultra-high pier body middle part is obviously higher than that of medium and low piers,and peak curvature in transverse direction is not synchronized with the capacity requirement ratio;judging weak parts of ultra-high piers based solely on peak curvature can’t reasonably evaluate their aseismic performance;the most unfavorable incident angle range for pier bottom is 0°-15°and 165°-180°,while the most unfavorable incident angle range for the transverse beam of ultra-high pier body is 60°-120°;the most unfavorable incident angle range for ultra-high pier top varies under different seismic intensities;the seismic vulnerability of supports is sensitive to changes in seismic intensity and incident angle,and exhibits different damage trends under seismic excitations of different working conditions;compared with bridge pie

关 键 词：桥梁工程 超高墩连续刚构桥 地震易损性 最不利入射角 震损规律 

分 类 号：U238[交通运输工程—道路与铁道工程]