洪奇门特大桥钢箱梁智能顶推施工关键技术

Key Techniques of Intelligent Incremental Launching Construction for Steel Box Girders of Hongqimen Bridge

南沙至中山高速公路洪奇门特大桥主桥为(80.5+222.5+520+222.5+80.5)m双塔双索面半飘浮体系钢箱梁斜拉桥。大桥位于珠三角近海冲积平原滨海区,边跨分别位于洪奇沥水道浅滩区及大堤内侧,钢箱梁采用边跨顶推、中跨悬臂架设的施工方案。考虑钢箱梁顶推距离长、重量大、工期长,为确保施工安全并提高工效,边跨钢箱梁采用智能顶推施工,研发了一套完整的全场景智能化成套技术。将非均匀载荷条件下桥梁顶推智能同步控制技术、基于动态监测数据驱动的桥梁顶推智能纠偏控制技术、基于数字孪生的桥梁顶推施工智能监测与控制系统相结合,使结构状态和设备控制形成联动,50个钢箱梁节段顶推施工平均工效可达3.8 m/h,实现了桥梁顶推施工全过程状态的实时监测、动态可视、预警及智能控制。

Carrying a section of the Nansha-Zhongshan Expressway,the main bridge of Hongqimen Bridge is a steel box girder cable-stayed bridge of a semi-floating system.The bridge,which is located in the coastal area of the coastal alluvial plain in the Pearl River Delta,has two pylons that create a main span of 520 m,flanged by a side span of 222.5 m(in the shoal area of Hongqili Waterway)and a secondary side span of 80.5 m(on the waterway side of the dike)on each side.The steel box girders in the side spans were incrementally launched and the steel box girder in the main span were cantilever-assembled.To combat the problems,including the long incremental launching distance,heavy launching weight and long construction schedule,an intelligent incremental launching construction was selected for the steel box girders in the side spans,to ensure the construction safety and efficiency.A complete set of all-scene intelligent construction techniques were employed,which integrates the intelligent synchronized incremental launching control technique under non-uniform loads,intelligent bias correction control techniques driven by dynamic monitoring data,and the intelligent incremental launching monitoring and control system,to allow the coordinated control of the structural states and equipment.The average incremental launching efficiency of 50 steel box girder segments reaches 3.8 m/h,achieving the real-time monitoring,dynamic visualization,early warning,and intelligent control of the full incremental launching process.