钢桁梁跨繁忙四线铁路拖拉式顶推施工技术

针对新建京雄城际铁路1-64 m钢桁梁跨繁忙京沪既有铁路存在施工安全风险大、临时支墩设置受限及天窗时间要求严格等难点,通过施工现场调查、方案论证验算选择拖拉式顶推施工。实施中采用在铁路限界外增设临时支墩、预留拖拉试验段、增加前导梁及后端配重等措施保证顶推安全,并在导梁前端墩顶设置反力支架及连续千斤顶实现钢桁梁纵向连续移动。顶推作业针对跨越铁路天窗点要求,对每个天窗点内作业内容及工况进行划分,通过各类措施优化实现安全快速跨越繁忙营运线路,可为类似工程施工提供参考。

Dragging-type Incremental Launching Construction Technology for Steel Truss Girder Across Busy Four-line Railway

For the newly-built Beijing-Xiong*an Intercity Railway,there are some difficulties in 1-64 m steel truss girder across busy Beijing-Shanghai railways,such as high safety risks in construction,limited temporary piers and strict requirements for the reserved time.Thus,the dragging-type incremental launching construction method was chosen through investigation of the site and program demonstration.During the implementation,several measures were taken to guarantee the pushing security in the construction,such as the temporary support piers were added outside railway clearances,the pulling test section was reserved and the front guide beam and the back end balance weight were used.And the reaction frame and the continuous lifting jack were set on the pier top of guide beam leading end,so as to realize the goal that steel truss girder could move continuously in the longitudinal direction.According to the requirements of the reserved time,the working content and conditions were divided in the pushing construction,and crossing busy operation lines was realized in a safe and fast manner by optimizing various measures,which could provide reference for similar engineering construction.