特大型钢沉井浮运封舱板结构设计研究

Research on structure design of floating-aid sealing boards for extra large steel caisson

钢沉井因自重较大,通常需要借助助浮结构浮运至桥位进行后续施工。目前的封顶式助浮结构对气密性要求很高,而整体封底式助浮结构存在整体拆除困难等显著缺点。为了解决这些问题,提出一种拆卸方便、加工精度高、吃水深度可调节的分舱封底式助浮封舱板结构。依托常泰长江大桥5号墩沉井项目,详细介绍了该分舱封底式助浮封舱板的结构及施工方案。在此基础上,采用有限元分析方法对封舱板在不同工况下的强度与刚度进行了模拟计算,验证了此结构的可行性和合理性。本结构的应用圆满完成了常泰长江大桥5号墩沉井的浮运任务,并在拆除后作为施工平台使用,成功节省了成本及工期,为钢沉井浮运施工技术的优化设计提供了一种新思路。

The steel caisson usually needs to be floated to the bridge location with the aid of the floating structure for subsequent construction due to its heavy weight.The current capped floating-aid structure has high requirements for air tightness,and the integral closed bottom floating-aid structure has significant shortcomings such as difficulty in overall removal.In order to solve these problems,a sub-tank bottom-closing floating-aid sealing board structure with convenient disassembly,high processing precision and adjustable draft was proposed.Relying on the No.5 pier caisson project of Changtai Yangtze River Bridge,the structure and construction plan of the sub-tank bottom-closing floating-aid sealing boards were introduced in detail.On this basis,the finite element analysis method was used to simulate the strength and stiffness of the sealing board under different working conditions,which had verified the feasibility and rationality of this structure.The application of this structure successfully completed the floating task of the No.5 pier caisson of Changtai Yangtze River Bridge,and was used as a construction platform after demolition,which successfully saved costs and construction period.It provides a new idea of the optimal design for floating transportation construction technology of steel caisson.