大跨度斜拉桥辅助墩钢箱梁段分块吊装设计与施工方案

Block Hoisting Design and Construction Scheme of Steel Box Girder Section of Auxiliary Pier of Long⁃span Cable⁃stayed Bridge

一座跨长江的大跨度钢箱梁斜拉桥的辅助墩钢箱梁与墩身存在空间冲突,梁段无法采用桥面吊机从桥下起吊安装,且南岸边跨位于浅水区,运梁船无法停靠,无法采用大型浮吊直接吊装就位,而大型履带吊机站位和现有建筑物等位置上有冲突。针对这一问题,提出了将辅助墩钢箱梁段进行分块吊装的方案。分块后可减小吊装重量,便于使用小型履带吊机,可以满足施工场地、空间等要求。本文介绍了梁段分块设计原则,给出了辅助墩钢箱梁分块、运输及吊装方案,并通过数值模拟进行验算。结果表明,运输及吊装过程中各工况下梁段各部分的应力与变形均满足设计及规范要求。梁段分块吊装施工保证了现场施工的连续性,提高了施工方案的可操作性及经济性。

The auxiliary pier steel box girder of a long-span steel box girder cable-stayed bridge crossing the Yangtze River has space conflict with the pier body.The girder section cannot be lifted and installed from underbridge by using the bridge deck crane,and the south bank side span is located in the shallow water area.The girder carrier cannot stop and cannot be directly lifted in place by the large floating crane,while the position of the large crawler crane conflicts with the existing buildings.To solve this problem,a scheme of block hoisting of steel box girder section of auxiliary pier was proposed.The lifting weight can be reduced after blocking,which is convenient for the use of small crawler crane and can meet the requirements of construction site and space.This paper introduced the design principle of girder section block,and put forward the blocking,transportation and hoisting scheme of auxiliary pier steel box girder,which was checked by numerical simulation.The results show that the stress and deformation of each part of the girder section under various working conditions during transportation and hoisting could meet the requirements of the design and specifications.The block hoisting construction of girder section ensures the continuity of on-site construction and improves the operability and economy of the construction scheme.