非对称施工荷载下斜拉悬索协作体系桥合理成桥状态研究  

Research on Reasonable Finished State of Cable-Stayed Suspension Bridge under Asymmetric Construction Load

作　　者：毛伟琦 姚森[2] 赵吉祥[2] 叶华文 蒋成川[1] 李小珍 MAO Weiqi;YAO Sen;ZHAO Jixiang;YE Huawen;JIANG Chengchuan;LI Xiaozhen(School of Civil Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China;China Railway Bridge Bureau Group Corporation,Wuhan Hubei 430034,China;National Key Laboratory of Bridge Intelligent and Green Construction,Railway Bridge Bureau Group Corporation,Wuhan Hubei 430034,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中铁大桥局集团有限公司,湖北武汉430034 [3]中铁大桥局集团有限公司桥梁智能与绿色建造全国重点实验室,湖北武汉430034

出　　处：《中国铁道科学》2024年第6期121-129,共9页China Railway Science

基　　金：国家重点研发计划项目(2023YFB2604403);中国中铁股份有限公司科技研究开发计划项目(2023-专项-02)。

摘　　要：为研究非对称施工荷载对斜拉悬索协作体系桥的合理成桥状态,以主跨为988 m的G3铜陵长江公铁两用钢桁加劲梁桥架设施工为工程背景,采用数值方法建立斜拉悬索协作体系桥的空间非线性有限元模型,对倒拆施工中非对称和对称施工荷载作用下千米级柔性桥梁结构受力、变形、合龙调整措施及合理成桥状态进行研究。结果表明:对称和非对称施工荷载下斜拉悬索协作体系桥的结构响应差异不大,非对称施工荷载下结构内力更小,但主梁上弦杆的最大位移增大2 m;合龙口梁段间宽度比合龙段小,梁段高差为7.6 cm,采用合龙口处施加5000 kN顶推力和临时吊索300 kN张拉力的调整措施,能有效调整合龙口几何形态,满足合龙施工要求;全桥合龙后主桁跨中区域呈上拱趋势,最大竖向位移为2.6 m,缆索过渡区斜拉索张拉完成后主桁上拱曲率增大,最大竖向位移为2.9 m,完成二恒铺装后主梁可达到合理设计线形。In order to study the effect of asymmetric construction loads on the reasonable finished state of cablestayed suspension bridge,taking the construction of the G3 Tongling Yangtze River dual-purpose steel truss stiffening girder bridge with a main span of 988 m as the project background,a spatial nonlinear finite element model of cable-stayed suspension bridge is established through numerical method,to study the stress,deformation,closure adjustment measures and the reasonable finished state of the kilometer-span flexible bridge structures under asymmetric and symmetric construction loads.The results indicate that,the structural responses of the cable-stayed suspension bridge system do not differ significantly under symmetric and asymmetric construction loads,but the internal forces of the structure are smaller under asymmetric construction loads,with an increase in the maximum displacement of the main girder’s top chord by 2 m.The space between the beam segments at the closure gap is smaller than that at the closure section,with a height difference of 7.6 cm between the beam segments.Adjustment measures,including the application of a 5000 kN pushing force at the closure gap and tensioning temporary hangers with a force of 300 kN,can effectively adjust the geometric shape of the closure gap to meet the closure construction requirements.After the closure of the entire bridge,the midspan area of the main truss exhibits an upward arching trend,with a maximum vertical displacement of 2.6 m.Upon implementation of stay cables in the cable transition zone,the upward curvature of the main truss increases,with a maximum vertical displacement reaching 2.9 m,and finally the main girder achieves the desired design alignment after the installation of the secondary permanent pavement.

关 键 词：公路铁路两用桥 斜拉悬索协作体系 钢桁加劲梁 非对称施工 荷载 合理成桥状态 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]