援孟八桥深水钢吊箱围堰设计

以中国援助孟加拉国第八桥项目为依托,对比了各类常见钢围堰的优缺点,并结合项目实际情况选择钢吊箱、钢板桩作为主桥基础施工的围护结构。主桥跨中处深水基础采用钢吊箱围堰施工,钢吊箱围堰通过吊箱钢侧板和底板上的混凝土封底形成封闭的止水结构,为深水基础的施工提供操作空间及施工条件。本文从设计思路、结构形式及各工况的结构验算等方面进行阐述,研究表明,该钢吊箱结构设计安全可靠,传力明确合理。此外,该钢吊箱结构在现场实际施工中具有良好的止水和支护效果,为后期指导同类型钢吊箱设计与施工提供有效依据。

Structural Design Related to Steel Cofferdam for Deep Water Foundation of the Eighth Bridge of Bangladesh Aided by China

Based on the eighth bridge of Bangladesh aided by China,the advantages and disadvantages of all kinds of space enclosing structures had been contrasted.Combining the actual situation of the project,steel cofferdams and suspension box-cofferdams had been elected as the space enclosing structure for foundation construction of the main bridge in deep water.The suspension box-cofferdam was elected to accomplish construction of the deep water foundation in the midspan of main bridge.The steel cofferdam utilized side steel moulding plates and sub-sealing concrete in the baseplate as the sealing structure,which provided operating space and application condition for foundation construction in deep water.The paper expounded the design thought,structural style and calculation of all kinds of working conditions.Research indicates the steel cofferdam is safe,reliable and convenient,whose mechanical property is clear and reasonable.In addition,the steel cofferdam has achieved commendable supporting and water-plugging results in the process of construction,which provides effective evidence for the steel cofferdam design and construction of similar bridges.