大跨度钢管混凝土系杆拱桥吊杆索力分析  

Analysis of suspension cable force of large-span steel tube concrete tied arch bridge

作　　者：王宪玉 王兴武 梁孝 周敏 杜永峰[1] WANG Xianyu;WANG Xingwu;LIANG Xiao;ZHOU Min;DU Yongfeng(Institute of Earthquake Prevention and Disaster Mitigation,Lanzhou University of Technology,Lanzhou 730030,China;Gansu Transportation Planning,Survey and Design Institute Co.,Ltd.,Lanzhou 730030,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Neijiang Normal University,Neijiang 641000,China)

机构地区：[1]兰州理工大学防震减灾研究所,兰州730030 [2]甘肃省交通规划勘察设计院股份有限公司,兰州730030 [3]西南交通大学土木工程学院,成都610031 [4]内江师范学院,四川内江641000

出　　处：《振动与冲击》2023年第17期306-313,共8页Journal of Vibration and Shock

摘　　要：针对大跨度钢管混凝土系杆拱桥吊杆索力问题,在基于能量法推导不同约束条件索力公式的基础上,结合工程实例,从吊杆设计阶段索力的优化、成桥阶段索力的实测、运营阶段索力抗弯刚度的影响三个方面进行系统分析并给予相应优化建议。研究结果表明:应用能量法推导的索力公式是可行的;设计阶段优化后吊杆索力更为均匀、系梁位移更加合理;应用频率法测试吊杆索力时,测试点位宜放在吊杆L/6~L/4处,尽可能远离吊杆两端并避免放在阵型的模态节点处,以减少端部低频信号对基频的影响及出现“漏频”现象;吊杆计算抗弯刚度与运营阶段实际抗弯刚度存在差异,导致索力测量值与结构实际索力存在较大差异,针对这一问题提出成桥阶段应测量吊杆实际抗弯刚度的方法,可有效减小索力测量误差,为桥梁运营阶段索力的准确测试提供计算依据。Here,aiming at the problem of suspension cable force in large-span steel tube concrete tied arch bridge,based on derivation of cable force formulas under different constraint conditions using the energy method,and combined with engineering examples,a systematic analysis was conducted from 3 aspects of cable force optimization during design phase of suspension rod,measurement of cable force during bridge completion phase and effects of cable bending stiffness during operation phase,the corresponding optimization suggestions were given.The study results showed that cable force formulas derived with the energy method are feasible;after optimization in design stage,suspension rod cable forces are more uniform and displacements of tie beams are more reasonable;when using the frequency method to test cable forces of suspension rods,testing points should be placed at L/6-L/4 of suspension rods,these positions are as far as possible from both ends of suspension rods and avoid being placed at nodes of modal shapes to reduce effects of low-frequency signals at both ends on fundamental frequency and occurrence of"frequency leakage"phenomenon;there is a difference between the calculated bending stiffness of suspension rod and its actual bending stiffness during operation stage to cause a larger difference between the measured cable force and the actual structure cable force;aiming at this problem,a method to measure the actual bending stiffness of suspension rod during bridge completion stage is proposed to effectively reduce the measurement error of cable force and provide a calculation basis for accurately testing cable force during bridge operation stage.

关 键 词：钢管混凝土系杆拱桥 能量法 优化 吊杆索力 频率法 抗弯刚度 

分 类 号：U24[交通运输工程—道路与铁道工程]