外海斜拉桥大悬臂钢箱梁防台风设计

Anti-typhoon Design of Large Cantilever Steel Box Girder of Offshore Cable-stayed Bridge

港珠澳大桥江海直达船航道桥设计为中央单索面钢索塔钢箱梁三塔斜拉桥,桥跨布置为110m+129m+258m+258m+129m+110m,索塔为全钢结构,采用工厂预制、现场整体吊装的施工工艺。受138#钢塔出运时间的限制,使得主桥贯通前的施工组织均处于极为不利的台风季节,所以到合龙前较长时段139#及140#钢箱梁均处于最不利的大悬臂工况。以139#号墩大悬臂钢箱梁为研究背景,介绍了大悬臂钢箱梁防台风设计方案,并选取典型工况进行有限元计算仿真分析,验证方案结构的可靠性。所提方案不仅为港珠澳大桥的顺利合龙提供了可靠的技术保障,更为以后同类工程的防台风施工提供了宝贵的参考。

The River-Sea Channel Bridge of Hong Kong-Zhuhai-Macao Bridge is a central single-plane steel cable pylon steel box girder three-pylon cable-stayed bridge. The span arrangement is(110+129+258+258+258+129+110) m,The cable pylon is a full steel structure prefabricated in manufactory by the construction technology of field integral hoisting. Limited by the delivery time of 138 # steel pylon,the construction organization before the running through of the main bridge is in a very unfavorable typhoon season. Taking 139 # pier large cantilever steel box girder as the study background, this paper introduces the anti-typhoon design scheme of large cantilever steel box girder, and selects the typical constructionsituation to carry out the finite element calculation and simulation analysis in order to verify the reliability of the scheme structure. The mentioned scheme can not only provide the reliable technical guarantee for the smooth closure of Hong Kong-Zhuhai-Macao Bridge, but also provide a valuable reference for the anti-typhoon construction of the similar projects in the future.