平潭海峡公铁两用大桥通航孔桥桥塔施工关键技术

平潭海峡公铁两用大桥处于典型的大风海洋环境,其FPZQ-3标段的3座通航孔桥均为双塔双索面钢桁-混凝土混合梁斜拉桥,均采用H形钢筋混凝土桥塔,塔身最高达200m。塔柱标准节段长6m,采用液压爬模施工,在爬模架体外侧采用冲孔钢板网进行全封闭防风;下横梁采用钢管支架施工、上横梁采用钢牛腿+支架施工,上、下横梁与塔柱均采用异步施工,在下横梁下方设1道空间桁架式横撑进行临时锁定;每个桥塔配备2台D1100-63V型塔吊进行整体吊装。

Key Techniques for Construction of Pylon of Channel Bridge of Pingtan Straits Rail-cum-Road Bridge

The Pingtan Straits Rail-cum-Road Bridge is located in a typical windy marine environment. The three navigable span bridges in the FPZQ-3 section of the bridge are all cable-stayed bridges which consist of double pylons, double cable planes, and steel truss-concrete hybrid girders, and H-shaped reinforced concrete pylons with a maximum height of 200 m are adopted for all the bridges. The standard section of a pylon column is 6 m long, which is constructed by hydraulic creeping formwork. The outside of the creeping formwork is made of perforated steel plate for wind-break. In the construction of lower beam, steel tube supports are adopted;in the construction of the upper beam, the steel brackets + supports are adopted;meanwhile, in the construction of the upper and lower beams and pylon column, an asynchronous method is adopted;a space truss type transverse brace is set below the lower beam for temporary locking;each bridge pylon is equipped with two D1100-63V pylon cranes for overall hoisting.