【作者】 刘杰文；

【导师】 李亚东；

【作者基本信息】 西南交通大学 ， 桥梁及隧道工程， 2006， 硕士

【摘要】 桥梁深水基础的修建，主要困难在于防水、防土，甚至防冲刷、防滑坡等。使用围堰配合施工的目的，就是在堰内施工和修筑基础时，使堰外的水和土不至于大量涌进堰内，并且待基础、墩台修筑出水面后又可将其拆除，避免堵塞水流和航道。随着深水基础施工技术和机械的发展，吊箱围堰在高桩承台施工中的应用日益广泛。 大型钢吊箱围堰在工厂整体制造成型、整体下水并浮运至墩位进行定位，是现代特大型桥梁深水基础施工的一个发展方向，其可以提高钢吊箱围堰的制造精度，减少在墩位处现场拼装的水上作业量。整体制造浮运的钢吊箱围堰集钻孔桩施工平台、钢护筒插打导向结构及承台、墩身施工挡水围堰等多种功能于一身，可以大大缩短钻孔桩施工完毕后至开始承台施工的工序转换时间，缩短整个基础的施工时间。但围堰整体制造成型后结构庞大，对锚定系统投设及围堰的精确定位标准等均有特殊的要求，并给围堰浮运拖带及定位等带来一系列的困难。 论文以武汉天兴洲长江大桥2#墩深水基础为工程实例，详细介绍了“大型钢吊箱整体浮运锚墩预施拉力定位、兼作钻孔平台施工技术”施工技术。主要包括大型钢吊箱围堰和锚墩系统的设计、大型钢吊箱围堰的制作和整体下河、大型钢吊箱围堰的浮运及初定位、大型钢吊箱围堰的精确定位等一系列施工方法。论文研究成果对今后大型桥梁深水基础施工具有重要参考价值。更多还原

【Abstract】 The most common difficulties during the construction of deep-water foundations for bridges are water-proofing, soil-proofing, anti-scouring and landslide etc. The purpose to construct a cofferdam is to prevent the water and soil outside the cofferdam from rushing into the cofferdam during cofferdam construction and foundation construction. The cofferdam shall be dismantled after the foundation, abutment and pier being constructed above the water level in order not to block the waterway and the stream. Double-wall steel cofferdam is one of widely used waterproofing cofferdam for the construction of bridge deep foundation. With the development of construction technologies and mechanical structures about deep-water foundation, large-scale suspended steel cofferdam has being applied widely for construction of high-rise-cap pile foundation.Manufacturing the large-scale suspended steel cofferdam in the factory and locating the cofferdam through floating-transportion to the pier position is one of development directions of the deep-water foundation construction for modern long span bridges. This technique can increase the manufacturing accuracy of the large-scale suspended steel cofferdam and decrease the assembling work in situ. The whole manufactured and float-transported large-scale suspended steel cofferdam integrates various functions together, such as being a construction platform for drilling holes for piles, an oriented structure for driving of steel casing tubes, a water-blocking cofferdam for construction of pile caps and pier shaft etc. It can consumedly shorten the transition time between the ending of pile drilling construction and the beginning of pile caps construction, and so shorten the whole foundation construction period. However, the structural size of this type of cofferdam is huge when it was wholly manufactured to the shape, also it has special requirements for anchor-pier system and the location precision of cofferdam etc., thus bringing a series of difficulties in cofferdam’s floating-transportation, dragging and locating.更多还原