【摘要】 洞庭湖特大桥主桥为三塔双索面钢箱钢桁组合梁铁路斜拉桥,钢梁采用适合大跨度三塔重载铁路斜拉桥受力特点的钢箱-钢桁组合新结构。组合结构主梁分两阶段成桥,先架设、合龙钢箱梁,然后在其上面拼装、合龙钢桁梁,钢梁制作安装精度要求高,施工技术难度大。边跨钢箱梁采用多点三向自平衡大行程步履式顶推施工技术,3号、5号墩钢箱梁采用单悬臂拼装,4号墩钢箱梁采用双悬臂对称拼装,顺利实现了箱-桁组合新结构主梁的钢箱梁无配切、钢桁梁无配板合龙。更多还原

【Abstract】 The main bridge of Dongting Lake Extra-Large Bridge is a three-tower and double-cable box-truss composite beam cable-stayed bridge. The steel beam adopts a new structure of box-truss composite beam which is suitable for the stress characteristics of long-span three-tower heavy-duty railway cable-stayed bridge. The construction process of the main beam of the combined structure was divided into two stages into a bridge. The steel box girders were first erected and assembled, and then the steel truss girders for final closure were erected and assembled above the steel box girders. High installation accuracy was required during the manufacture of steel beam, and the construction technique was difficult. An innovation scientific and reasonable construction control method was proposed, and it has successfully realized the final closure of the box-truss combination, which the new structure is the steel box girder without matching cutting and the steel truss without matching plate.更多还原