钢围堰深水大体积砼封底施工技术

Construction Techniques for the Sealing of the Bottom of the Deep-Water Large-Volume Concrete with Steel Cofferdam

大体积、大区域钢围堰水下混凝土封底施工具有方量大、面积广、浇筑时间长、混凝土质量控制严等特点。结合某特大桥水中主桥主墩双壁钢围堰的拼装、下沉以及基底找平后进行双壁钢围堰封底施工的实际工况,从平台搭设、料斗及导管布设、施工组织、砼浇筑控制、封底施工质量控制及常见问题的处理等方面介绍了大体积砼封底施工的相关技术,可为类似项目提供借鉴。

As far as the under-water bottom-sealing construction of bulky,large-area concrete with a steel cofferdam is concerned,it involves the difficulties of being large in volume,vast in area,long in pouring duration,and strict in concrete quality control.With the construction of the assembling and sinking of the steel cofferdam,and the post-bottom-leveling bottom-sealing construction of the dual-walled steel cofferdam for the main bridge and its main piers in water of a certain mega bridge as a practical example,in the paper introduced in detail are the relevant techniques for the bottom sealing construction of bulky concrete,such as the erection of platforms,the lay-out of bunkers and guide tubes,the organization of construction,the control of pouring concrete,the quality control of the bottom sealing operation,and the solution of common problems.The project may serve as a useful reference for other projects of similar types.