摘要
杭州市彭埠大桥主桥为(73.4+122+4×240+122+73.4)m公轨两用多跨悬链形上加劲钢桁梁桥,采用双层桥面布置,上层通行双向8车道公路,下层通行双线地铁与两侧各5.5 m宽的慢行系统。主桥钢梁横向采用2片主桁,桁宽36.8 m,桁高12 m,节间长10、12 m,主桁钢梁节点为全焊接整体节点,采用两节间半桁片结构设计及拼装方案;上、下层桥面均采用正交异性钢桥面板,竖撑杆位置与上层公路桥面纵梁及下层轨道桥面边纵梁位置对应;为改善上、下层横梁受力,钢梁所有节点处均设置横向联结系;钢梁设置悬链形上加劲弦杆,杆件全高从1.2 m渐变为2.8 m。钢梁采用先架设平弦部分钢桁梁,再施工上加劲系统的总体顺序,平弦部分钢桁梁架设采取双向顶推施工。施工过程中钢梁最大顶推重量为22000 t,最大顶推长度为565 m,最大悬臂长度为80 m。采用MIDAS Civil软件对该桥运营阶段及施工阶段进行受力验算,结果表明该桥结构刚度较大,运营阶段及施工阶段钢梁受力满足规范要求。
The main bridge of Pengbu Bridge in Hangzhou is a multi-span steel truss girder bridge stiffened with rigid catenarian suspension system.The bridge is a double-decker and has four main spans of 240 m,two side spans of 122 m and two end spans of 73.4 m,accommodating 8 vehicle lanes on the upper deck(four lanes in each direction)as well as two metro lines flanked with two 5.5 m wide pedestrian/cycle/motorcycle lanes on the lower deck.The superstructure of the main bridge consists of two lateral trusses spaced 36.8 m along bridge width,the trusses measure 12 m deep,to facilitate the construction,the trusses are assembled to 10 m-and 12 m-long panels with all-welded integral nodes.Two panels form a construction unit and the trusses do not have upper and lower lateral bracings,instead,equipped with upper and lower orthotropic steel plate deck systems.The locations of vertical struts coincide with the edge stringers of upper roadway deck and the edge stringers of the lower metro line deck.To improve the load bearing capacities of the upper and lower cross beams,lateral bracings are added at all the nodes of steel trusses.The superstructure is stiffened by the rigid catenarian suspension system with height varying from 1.2 m to 2.8 m.The steel trusses in the flat-chord sections were erected ahead of the stiffening suspension system,using two-way incremental launching method.The maximum incremental launching weight,distance and cantilever length reach 22000 t,565 m and 80 m,respectively.The load bearing behavior of the bridge in the construction and service stages were simulated in MIDAS Civil,and the results demonstrate that the bridge structure has a large safety margin,and the load bearing capacity of which at both the construction and service stages meet the code requirements.
作者
谢兰博
康晋
刘汉顺
XIE Lanbo;KANG Jin;LIU Hanshun(China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430056,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2023年第4期116-122,共7页
Bridge Construction
基金
浙江省交通运输厅科研计划项目(2019017)。
关键词
公轨两用桥
连续梁桥
上加劲钢桁梁
正交异性钢桥面板
顶推施工
受力验算
桥梁设计
bridge accommodating roadway and metro line
continuous girder bridge
steel truss girder stiffened with rigid cable
orthotropic steel deck plate
incremental launching
load bearing capacity checking
bridge design
