紧邻既有铁路大跨连续梁深水基础施工技术

摘要

随着我国铁路桥梁建设事业的高速发展，原有单线铁路增建、改建工程需求比较多，但由于土地资源的紧张及河道航运安全需要，在跨越等级河道上出现了大量紧邻既有桥梁建设的需求。但因新建线路与既有线路桥梁间距过小，施工作业场地严重受限，给新建桥梁的下部结构施工提出了更高的要求。文章以石门至长沙铁路复线沅江特大桥（62＋4×96＋92＋66）m连续梁桥下部结构施工为例，提出采用先成桩、后围堰的施工方法，详细介绍先搭建水上施工平台进行桩基施工，桩基施工完成后拆除平台，然后利用导向系统下沉双壁钢套箱进行封底，再进行承台基础施工的紧邻既有线大跨连续梁深水基础施工技术。%Along with the high speed development of railway bridge construction in China,there are more needs and more for the original single-track railway to be added and improved.However,in order to occupy the less land resources and meet the requirements of river shipping safety across the river level,a great number of bridges are required to be built adjacent to the existing bridge.As the spacing of bridge between new line and the existing line is too limited and the construction site is severely restricted,it is difficult to construct the new bridge substructure.As the case of the sub-structure construction of Yuanjiang special major Bridge (62 +4 ×96 +92 +66 )m on Changsha-Shimen double line, this paper presents such construction method as pile construction first and cofferdam second.firstly water construction platform is made when pile foundation is constructed and removed after of the pile foundation is completed,then the guide system is utilized for sinking double-wall steel case and bottom sealing.For further details,you can read the whole text.