高铁桥梁上跨既有营业线简支箱梁横移施工技术

Key Transverse Moving Techniques for Simply-Supported Beams of a High-Speed Railway Bridge Crossing Existing Railways

新建福州至厦门铁路上行联络线湖边特大桥上跨既有福厦线湖地里大桥,设计为32 m简支混凝土箱梁。为确保该简支箱梁施工时既有营业线运营安全,简支箱梁施工采用墩旁线外支架现浇、横移就位施工技术。综合考虑天窗点作业时间限制、营业线高空施工安全,在常规的支架现浇、横移施工技术基础上,采用现浇支架与横移系统联合设计,增加了支架上箱梁横移的稳定性;设计了鱼腹式异形滑道梁,滑道梁分段设计、吊装,降低了营业线吊装难度,确保吊装安全;改进了滑轮导向限位装置,利用滑座两侧的钢轮引导及限位滑移,确保了横移就位的准确性。采用的施工技术降低了上跨施工安全隐患,节约了施工成本,加快了施工进度,有效解决了新建桥梁上跨既有营业线的施工难题。

The Hubian Bridge,which carries part of the upline of the Fuzhou-Xiamen Railway,crosses the Hulidi Bridge of the existing Fuzhou-Xiamen Railway.The bridge is a 32 m-span simply-supported concrete box beam bridge.To ensure the safe operation of the existing railway,the simply-supported concrete box beam were cast in situ aside the piers first,and then transversely moved into position.To take good advantage of the limited window time and ensure the safety of overhead construction,the concrete box beam was cast in situ on the scaffolds that are supplemented with the extra scaffolds for beam transverse movement,intending to improve the stability of the transverse movement of box beam.A kind of fish-belly shaped beam was designed to carry sliding rails,which was manufactured into several segments to ease the erection and ensure the erection quality.The restrainers to guide and limit the pulleys were improved,the steel wheels on the two sides of the sliding shoe were able to guide and limit the sliding of the pulleys so as to ensure the concrete box beam could be transversely moved into position with accuracy.The proposed transverse moving construction method can reduce the construction safety risk of the overpass structure,save construction costs and time,providing a solution for the construction of bridges crossing existing railways.