津秦客运专线113m简支系杆拱桥平转施工技术

津秦客运专线丰南特大桥以113 m简支系杆拱桥同时跨越津山铁路下行线和丰胥联络线,为不影响津山铁路和丰胥联络线的正常运行,该桥上部结构采用异位支架成桥,整体平转至设计桥位的方法施工.异位支架由钻孔桩基础、钢管桩及贝雷梁组成,位于津山线的下行线外侧并与之平行.平转系统由大吨位球形铰支座、临时墩和圆弧形跨线滑道梁组成.拱桥形成稳定的结构体系后,沿圆弧形滑道梁顶推约33.53m,以球形铰支座为中心平转约17°后跨越既有线上空到达设计桥位,在梁体两端交替进行项、落梁作业,使系杆拱桥落座于永久桥墩的支座顶.

Construction Techniques for Horizontal Rotation of 113-m Span Simply-Supported Tied Arch Bridge on Tianjin-Qinhuangdao Passenger Dedicated Railway

The Fengnan Bridge on Tianjin-Qinhuangdao Passenger Dedicated Railway crosses both the down line of Tianjin-Shanhaiguan Railway and the link line of Fengxu Railway with its 113-m span simply-supported tied arch bridge.In order not to interfere with the normal operation of the two railway lines under the bridge,the superstructure of the bridge was constructed by the method of completing the whole structure on scaffolding closely off the designed bridge site and integrally horizontally rotating the structure in place to the bridge site.The scaffolding had three parts of the bored pile foundations,steel pipe piles and Bailey truss and was located outside and in parallel to the down line of the Tianjin-Shanhaiguan Railway.The horizontal rotation system for erection of the bridge was composed of the large tonnage spherical hinge bearing,temporary piers and curved slipway beams over the railway lines.After the tied arch bridge became a stable structure system,the bridge was pushed about 33.53 m along the slipway beams,horizontally rotated about 17° around the center of the spherical hinge bearing and the bridge would cross the existing railway lines to the designed bridge site.At the both ends of the girder of the bridge,the girder was then jacked up or down alternatively to finally seat the bridge on the bearings atop the permanent piers.