复杂海域桥塔墩防撞吊箱围堰施工关键技术  

Key Construction Techniques for Anti-Collision Box Cofferdam of Pylon Piers in Complex Sea Environment

作　　者：张红心[1] ZHANG Hong-xin(China Railway Major Bridge Engineering Group Co., Ltd., Wuhan 430050, China)

机构地区：[1]中国中铁大桥局集团有限公司

出　　处：《桥梁建设》2019年第5期103-107,共5页Bridge Construction

摘　　要：平潭海峡公铁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,桥塔墩承台采用哑铃形防撞吊箱围堰施工。围堰采用“永-临”结合的原则设计,施工后将围堰作为防撞箱使用。围堰采用工厂化制造,整体拼装后利用滑道将其滑移出厂,减少了现场作业时间;围堰分2次吊装,利用千斤顶精准就位技术,保证了围堰在恶劣海况下的精准对接施工;采用三层限位、斜撑和消波孔技术,克服了波浪对围堰施工的影响;系梁区采用系梁桁架,解决了系梁区的抗浮和抗沉问题;采用底板、侧板可拆卸技术,满足了后期防撞箱侧板更换要求;采用密封胶等防渗措施,保证了围堰的止水效果。The Pingtan Straits Rail-cum-Road Bridge is a typical sea-crossing bridge exposed to harsh winds. The 3 navigable bridges in Contract FPZQ-3 of the project are all steel truss-concrete hybrid girder cable-stayed bridges, each with two pylons and double cable planes. The pylons are all H-shaped reinforced concrete pylons. The pile cap of each pylon pier is constructed with the aid of the dumbbell-shaped anti-collision box cofferdam. The cofferdam consists of both permanent and temporary components, after the completion of the pile cap construction, which can be used as the box to prevent ship collision. The cofferdam is manufactured in a workshop and slipped out of the workshop by sliding rails after being integrally assembled, so as to cut down the time used for in-situ operation. The cofferdam is hoisted twice and lowered accurately into position by jacks to realize the precise connection of cofferdam lifts in the harsh sea environment. Three layers of restraints, inclined struts and wave absorbing holes are added to overcome the effects of waves on the cofferdam construction. In the tie beam zone, trusses are used to resolve the problems of buoyancy and sinking. The bottom and wall plates are all detachable for the future replacement. The cofferdam is sealed by sealant to assure its waterproof effect.

关 键 词：跨海大桥 公路铁路两用桥 斜拉桥 哑铃形承台 防撞吊箱围堰 施工技术 

分 类 号：U448.121[建筑科学—桥梁与隧道工程] U445.556[交通运输工程—道路与铁道工程]