大跨钢管混凝土劲性骨架拱桥拱肋竖转施工抗风性能研究  

Research on Wind Resistance of Stiff-Skeleton Arch Ring of Long-Span Concrete-Filled Steel Tubular Arch Bridge During Vertical Rotation Construction

作　　者：魏宇 金正凯 WEI Yu;JIN Zheng-kai(China Railway Engineering Design and Consulting Group Co.,Ltd.,Beijing 100055,China)

机构地区：[1]中铁工程设计咨询集团有限公司,北京100055

出　　处：《桥梁建设》2023年第2期75-81,共7页Bridge Construction

基　　金：铁道部科技研究开发计划课题(2008G023-C)。

摘　　要：为保证大跨度钢管混凝土劲性骨架拱桥拱肋竖转施工过程的抗风安全,以某主跨342 m钢管混凝土劲性骨架拱桥拱肋竖转施工为背景,研究该桥劲性骨架拱肋在竖转施工过程中的抗风性能及抗风措施。根据竖转施工特点,采用ANSYS软件分别建立2种最不利施工状态(拱肋竖转临界状态和拱肋合龙前状态)有限元模型计算风致响应,提出设置浪风索的抗风措施以提高抗风稳定性。结果表明:拱肋在2种最不利施工状态下会产生显著的拱顶横向位移和拱脚转轴连杆应力,危及拱肋施工安全;设置浪风索能有效降低处于竖转施工阶段的拱肋在横风作用下的拱顶横向位移和拱脚转轴连杆应力,且浪风索应力满足要求,可保证竖转施工安全。浪风索截面面积对拱脚转轴连杆应力影响较小,对拱顶横向位移影响较大,同时考虑到施工中浪风索张拉力的不均匀性,设计时宜适当增加浪风索截面尺寸,以提升结构整体抗风安全储备。The research focuses on the wind resistant safety of the long-span concrete-filled steel tubular arch bridge during the vertical rotation construction of the stiff-skeleton arch ring.An existing bridge of similar type with a main span of 342 m is used as a case,to explore the wind resistance of the stiff-skeleton arch ring during vertical rotation construction and the wind protection measures.In accordance with the characteristics of vertical rotation construction,the finite element models of two most unfavorable construction conditions(the critical state of vertical rotation of the arch ring and the pre-closure state of the arch ring)were developed in ANSYS to calculate the wind responses of the structure.Wave wind cables were recommended to improve the wind-resistant stability of the bridge.It is shown that under these two most unfavorable conditions,there is significant transverse displacement at the arch crown and stresses in the tie rods of arch springing pivot during vertical rotation construction due to the cross wind.The forces of the wave wind cables meet the requirements,which are able to ensure the safety of vertical rotation construction.The cross-sectional area of the wave wind cable exerts minor influence on the stresses in the tie rods of arch springing pivot,but significant influence on the arch-crown transverse displacement.Considering the uneven tension of wave wind cables,it is proper to enlarge the cross-section of the wave wind cable to enhance the overall wind resistant safety margin of the bridge.

关 键 词：拱桥 钢管混凝土劲性骨架 拱肋竖转施工 风致响应 浪风索 有限元法 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U441.2[交通运输工程—道路与铁道工程]