南京夹江特大桥钢箱梁吊装膺架安拆施工技术

在城市高架桥及市区跨江河大桥建设过程中,主桥主梁形式常设计为钢箱梁结构。钢箱梁箱形截面抗扭刚度强,整体性能好,自重轻,外形轻巧美观,施工周期短。而在江河中大跨度悬索桥、系杆拱桥钢箱梁施工常考虑采用膺架吊装方案,因为该方法相对顶推法施工简单、安全、快速、高效,但是膺架一般工程量较大,施工时间紧,特别在遇到水深、通航、流速大、净空小等限制条件时,水中安装和拆除施工起来也相当困难。结合南京隧道夹江大桥右汊独塔自锚式悬索桥钢箱梁吊装工程实例,介绍利用舟桥器材拼组高架浮吊、导向定位船、龙门船吊等设备,在深水中进行大跨度钢箱梁膺架吊装安拆施工工艺及方法。

Construction Technology for the Installation and Demolition of Nanjing Jiajiang Bridge Steel Box Girder Hoisting Scaffolding

In the construction process of city viaduct and urban bridge across river, the main girder of the main form is of- ten designed as a steel box girder structure. Steel box section has the advantages of torsional stiffness, good overall perform- ance, light weight, beautiful shape and appearance, short construction period. But tied arch bridge steel box girder con- struction is usually considered in the construction of long span suspension bridge due to its relatively simple, sale, fast, ef- tlcient method compared with pushing construction, but the scaffohting engineering amount is larger, the construction time is tight, especially in the face of deep water, navigation, high velocity, low headroom constraints, installation and removal of the construction is very difficult. Combined with the engineering examples of Nanjing tunnel of Jiajiang bridge right branch of self anchored suspension bridge steel box girder, the paper introduces the pontoon bridge assembled overhead crane, ship positioning, Longmen crane equipment, large span steel scaffolding hoisting device and method and construc- tion technology of removal and installation of hoisting scaffolding for large span steel box girder in deep water.