基于易损性的铁路桥梁通行功能评估研究  

Research on Traffic Function Assessment of Post-Earthquake Railway Bridges Based on Vulnerability

作　　者：沈林白 洪彧[1] 李敬研 蒲黔辉[1] 文旭光 SHEN Linbai;HONG Yu;LI Jingyan;PU Qianhui;WEN Xuguang(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Guangxi Key Laboratory of International Join for China-ASEAN Comprehensive Transportation,Nanning University,Nanning 530200,China)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]广西中国-东盟综合交通国际联合重点实验室(南宁学院),南宁530200

出　　处：《铁道标准设计》2024年第10期98-105,共8页Railway Standard Design

基　　金：四川省科技计划项目(2021YJ0054);广西科技计划项目(桂科AA21077011);中央高校基本科研业务费-科技创新项目(2682022CX003)。

摘　　要：为对铁路桥梁震后状况进行合理评估,基于易损性构建了一套铁路桥梁震后通行能力评估方法,以国内常见铁路桥梁为参考,使用OpenSees建立了20座不同构造参数的4跨简支梁桥全桥有限元模型,基于耐震时程地震分析进行易损性与通行功能的评估,厘清了影响铁路桥梁地震损伤与通行能力的主要因素。研究表明:纵筋配筋率和剪跨比是影响铁路桥梁地震损伤的核心因素,轴压比是影响铁路桥梁地震损伤的主要因素,体积配箍率是影响铁路桥梁地震损伤的次要因素,为控制桥梁地震损伤,可以提高纵筋配筋率,降低剪跨比;配筋率增加通行能力会明显提升,剪跨比增加通行能力明显下降,配箍率和轴压比增加通行能力会小幅提升;纵筋配筋率与剪跨比是影响桥梁通行能力的主要因素,体积配箍率与轴压比是影响桥梁通行能力的次要因素,为保证通行能力最优,应适当提高纵筋配筋率或减小桥墩剪跨比,也可适当提高体积配箍率与轴压比。本研究提出的通行能力评估方法可以较好地评估桥梁结构通行功能,用于震后评估工作。In order to evaluate the post-earthquake condition of railway bridges,this study develops a method for evaluating the traffic function of railway bridges based on vulnerability.Taking common railway bridges in China as references,20 four-span simply-supported beam bridges with varying structural parameters were modeled in OpenSees for full-bridge finite element analysis.Seismic timehistory analysis was employed to evaluate both the vulnerability and traffic function of the bridges,clarifying the key factors influencing seismic damage and traffic function.The findings indicated that the longitudinal reinforcement ratio and shear span-to-depth ratio were the core factors affecting seismic damage,with the axial compression ratio also playing a significant role,while the volumetric stirrup ratio served as a secondary factor.To control seismic damage of the bridges,increasing the longitudinal reinforcement ratio and reducing the shear span-to-depth ratio were recommended.A higher reinforcement ratio significantly enhanced traffic capacity,while an increased shear span-to-depth ratio reduced it.Additionally,slight improvements in traffic capacity were observed with increases in the reinforcement ratio and axial compression ratio.The longitudinal reinforcement ratio and shear span-to-depth ratio were the main factors affecting the traffic function of the bridges,while the volumetric stirrup ratio and axial compression ratio were secondary.To ensure optimal traffic capacity,the longitudinal reinforcement ratio should be appropriately increased or the pier shear span-to-depth ratio be reduced,with modest increases in the volumetric stirrup ratio and axial compression ratio.The traffic capacity evaluation method proposed in this study provides an effective tool for assessing bridge functionality and is suitable for post-earthquake assessments.

关 键 词：铁路桥梁 易损性 通行功能 OPENSEES 耐震时程 

分 类 号：U24[交通运输工程—道路与铁道工程] U448.13[建筑科学—桥梁与隧道工程] U442.5