软土地区上跨既有铁路转体梁施工技术研究

西苕溪左线特大桥63#~66#墩(72+128+72)m单线转体梁为大跨度窄截面结构,上跨既有宣杭铁路线,桥区广布软土且施工点与运行线最小距离仅为3.36 m,存在施工干扰大、转体结构复杂、施工工艺繁琐等问题。对此,从既有线路基础加固防护、箱梁工装改进、转体精确控制等多个方面进行研究,设计采用了钢便梁加注浆锚杆挂网喷混加固技术,创新优化了一种内模架及钢绞线辅助牵引头,总结形成一套大跨度窄截面转体梁转体控制技术,从而保证转体连续梁的安全高效快速施工,以期为同类工程提供参考和借鉴。

Research on Construction Technology of Rotating Beam for Overcrossing the Existing Railway in Soft Soil Area

The No.63~No.66 pier single-line rotating beam of Xitiaoxi left line super-large bridge is long-span and narrow-section structure,it crosses the Xuancheng-Hangzhou railway line from above.The bridge area is covered with soft soil,and the minimum distance between construction point and operating railway line is only 3.36 m.Therefore,there are some problems such as large construction interference,complicated construction technology and complex rotating structure.Based on the above,the paper studies many aspects,such as the reinforcement of the existing railway line foundation,the improvement of the box girder tooling and the precise control of the rotating beam.Finally,the project adopts a strengthening technique of steel beam with slope protection,innovates an internal template and steel strand device,and summarizes a set of control techniques for long-span and narrow-section rotating beam,so as to ensure the safety,efficiency and rapid construction of the rotating continuous beam.The research of this paper can provide reference for similar projects.