摘要
宁安铁路安庆长江铁路大桥主桥为双塔多跨连续钢桁梁斜拉桥,该桥3号、4号墩均采用高桩承台基础。为解决桩基汛期施工风险大和3号墩深水无覆盖层斜岩面环境下桩基施工平台搭建难题,经方案比选,3号、4号墩基础采用先围堰(直径56m)后平台的双壁钢围堰施工方案。施工中采取了以下关键技术:3号墩围堰采用气囊法下河,4号墩围堰采用整体起吊下河;围堰采用无导向船重锚锚碇系统定位;采用活动插板法快速完成了斜岩面围堰底缺口封堵;围堰采取了分区封底施工。
The main bridge of Anqing Changjiang River Railway Bridge on Nanjing-Anqing Railway is a double-pylon and multi-span continuous steel truss girder cable-stayed bridge and the main piers No. 3 and No. 4 of the bridge are supported on the elevated pile cap foundations. To cope with the problems that the construction risk of the pile foundations would be high in the flood period and the setting-up of the working platform would be difficult for the foundation of the Pier No. 3 on the inclined rock surface in deepwater and without overburden, it was deter- mined through comparison that the construction scheme of building the circular double-wall steel boxed cofferdams （each being 56 m in diameter） for the Piers No. 3 and No. 4 first and setting up the platforms late would be adopted. In the process of the construction, the following key tech- niques were applied, i.e. the cofferdam for the Pier No. 3 was launched to the river by the air bag method and the cofferdam for the Pier No. 4 was integrally lifted down to the river. Both the cof- ferdams were positioned at the pier sites by the heavy anchor anchorage systems without utilizing the guiding barges. The opening at the bottom of the cofferdam on the inclined rock surface was fast blockaded by the movable inserted steel plate method and the bases of the two cofferdams were sealed by tremie concrete in areas.
出处
《桥梁建设》
EI
CSCD
北大核心
2012年第6期1-7,共7页
Bridge Construction
关键词
斜拉桥
基础
方案比选
钢围堰
桥梁施工
cable-stayed bridge~ foundation
scheme comparison
steel cofferdam
bridge construction
