新建商合杭铁路芜湖长江公铁大桥主桥为(99.3+238+588+224+85.3)m的钢箱板桁结合梁斜拉桥,主梁上层为板桁结合,下层为钢箱结合钢桁梁.该桥钢梁划分为89个铁路面梁段单元和94个公路面梁段单元,采用分段吊装施工,钢梁架设采用“浮吊辅助架设墩顶节段+桥面架梁吊机悬臂架设”的总体方案,设中跨合龙口.首先利用浮吊起吊,采用支架法架设2号和3号桥塔墩墩顶的3个钢梁节段,然后在公路桥面上各安装2台桥面架梁吊机进行双悬臂架设,悬臂架设至辅助墩前方时,利用浮吊起吊安装辅助墩墩顶钢梁节段;当悬臂架设至边墩前方时,采用“浮吊+支架”辅助桥面架梁吊机悬臂架设边墩墩顶钢梁节段;最后利用2号墩侧架梁吊机提升中跨合龙段进行中跨合龙.%The main bridge of Wuhu Changjiang River Rail-cum-Road Bridge on the newly built Shangqiu-Hefei-Hangzhou Railway is a steel box,plate and truss composite girder cablestayed bridge with span arrangement (99.3+238+588+224+85.3) m.The upper deck of the main girder of the bridge is the plate and truss composite girder while the lower deck is the steel box and truss composite girder.As is designed,the steel girder of the bridge is divided into totally 89 railway deck units and 94 highway deck units that are to be lifted and installed unit by unit.The steel girder is to be erected,using the general scheme of erecting the deck units atop the piers with the aid of the floating cranes+cantileveredly erecting the rest of the units mainly by means of the deck cranes.At the midspan of the central span,the closure gaps are arranged.Firstly,the floating cranes start the lifting and the 3 deck units atop the pylon piers No.2 and No.3 are erected,using the scaffolding method.Then,each 2 deck cranes are respectively installed on the highway deck and the two-side cantilever erection of the steel girder is carried out.When the cantilever erection reaches the front of the auxiliary piers,the floating cranes are used to lift and install the deck units atop the auxiliary piers.When the cantilever erection reaches the front of the side piers,the floating cranes+the scaffolding method are used to aid the deck cranes in cantileveredly erecting the deck units atop the side piers.Finally,the deck cranes on the side of the pier No.2 are used to lift the closure units at the midspan of the central span and to complete the closure of the steel girder.
展开▼
