沼泽区斜拉桥钢-混凝土叠合梁施工技术

Construction Technology of Steel-concrete Composite Beams of Cable-stayed Bridge in Swamp Area

珠海市洪鹤大桥主航道桥为主跨500m的双塔双索面钢-混凝土叠合梁斜拉桥,其3号主塔位于防洪大堤背水侧的沼泽区。结合现场施工环境特点,塔周梁段采用支架法不对称架设工艺,确保了防洪大堤的结构安全,克服了陆地施工环境、大型水上设备无法提供有效服务的困难。标准梁段采用桥面起重机双悬臂对称架设施工,探索了一种新型桥面起重机,辅助墩顶梁段采用支架辅助法施工。钢梁采用等温合龙工艺,先临时锁定,再配钻连接板螺栓孔,与传统合龙方法相比,降低了大规模螺栓孔群的匹配难度,加快了合龙施工速度,同时也保证了合龙质量。

The main bridge of the Honghe Bridge in Zhuhai is a steel-concrete composite beam cable-stayed bridge with double pylons,double cable planes,and the 500m main span.The No.3 main pylon is located in the swamp area on the back of the levee embankment.Limited by the construction environment on site,the asymmetrical installation technology of the bracket method is adopted for the beam sections around the pylon to ensure the safety of the levee,which overcomes the difficulty of the scarcity of effective services provided by water construction equipment.The standard beam sections are double cantilever installed symmetrically with an innovative crane,and beam sections on the auxiliary pier top are installed with support method.The steel beam adopts isothermal closure process,which is temporarily locked first,and then the bolt hole of the connecting plate is drilled.Compared with the traditional method,this technology reduced the difficulty of matching large-scale bolt groups,speed up the construction and guaranteed the quality at the same time.