坝陵河大桥钢桁加劲梁施工架设方案研究

Research on Erection Methods of Steel Stiffening Truss Girder for Baling River Bridge

首先研究了跨缆吊机架设法、缆索吊机架设法、桥面吊机悬臂拼装架设法和顶推架设法4种悬索桥钢桁加劲梁施工架设方法,根据坝陵河大桥的建设条件,综合考虑施工安全、质量、工期、环保和经济性等因素,推荐采用桥面吊机悬臂拼装架设法。在此基础上,研究了钢桁加劲梁在悬臂拼装过程中的3种连接方式:全铰法、无铰逐次刚接法和有铰逐次刚接法,综合考虑施工安全、质量和工期要求,推荐采用有铰逐次刚接法。此外,研究了钢桁加劲梁在悬臂拼装过程中架设前端吊索的牵引方案。最后,研究了靠索塔首次节段、标准节段以及合龙段等3个关键阶段的架设方案。桥面吊机悬臂拼装方案为我国西部地区大跨钢桁加劲梁悬索桥的设计和施工提供了1种新的方法。

Four methods of erecting steel stiffening truss girder of suspension bridge, including the deck lifting gantry crane method, the cable-mounted crane method, the cantilever erection method with derrick crane and the incremental launching method, were studied. Based on construction conditions of the bridge, according to the optimal combination of various factors such as construction safety, quality, period, environmental protection and economic performance, etc., the cantilever erection method with derrick crane was recommended for the bridge. On this basis, three categories of connection in cantilever erection methods, ineluding the all hinged method, the successive fully splicing method and the successive splicing with temporary erection hinge method, were studied. The successive splicing with temporary erection hinge method was recommended in the bridge with consideration of the requirements of construction safety, quality and time limit. In addition, the traction method of hangers at the top end during cantilever erection was studied. Finally, the erection method of three key stages, including the first and second segment near the pylon, the standard segment as well as the closure segment of steel stiffening truss girder, was studied.The cantilever erection method with derrick crane provides a new way for design and construction of long-span suspension bridge with steel stiffening truss girder in the western area of China.