宜宾金沙江公铁两用桥主墩基础施工技术  

Construction Techniques for Main Pier Foundations of Yibin Jinsha River Rail-cum-Road Bridge

作　　者：刘翠云[1] 代皓[1] 

机构地区：[1]中铁大桥局集团有限公司,湖北武汉430050

出　　处：《桥梁建设》2016年第2期97-102,共6页Bridge Construction

基　　金：中国中铁股份有限公司科技开发项目(2014-重大-04)~~

摘　　要：宜宾金沙江公铁两用桥主桥为(116+120+336+120+116)m五跨连续双层桥面系杆拱桥,主拱为336m钢箱系杆拱。2号、3号主墩均采用3.4m大直径钻孔桩基础。2号主墩基础采用筑岛施工方案。2号主墩承台开挖高度达24.0m,采用土钉墙防护技术对承台高边坡进行防护,降低现场施工难度。3号主墩基础采用双支栈桥+水上钻孔平台的施工方案,钻孔平台兼做水上提升站。3号主墩承台采用可重复利用的拆装式双壁钢套箱围堰施工技术,围堰侧板止水锁口钢管的两侧焊接月牙形锁口,方便插入和拔除,且止水效果好。The main bridge of Yibin Jinsha River Rail-cum-Road Bridge is a 5-span double-deck continuous bowstring arch bridge with span arrangement(116+120+336+120+116)m.The main arch of the bridge is the 336-m span steel box bowstring arch and the main piers No.2and No.3are all supported on the foundations of the3.4-m large diameter bored piles.The foundation for the pier No.2was constructed,using the scheme of artificial island.In the construction of the pile cap of the pier,the excavation depth reached 24.0mand the high slopes of the excavation were protected by the soil nail wall technique so as to reduce the construction difficulties in the field.The foundation for the pier No.3was constructed,using the scheme of double-support trestle+boring platform over water and the boring platform was concurrently used as the hoisting station over water.The pile cap of the pier was constructed by the reusable detachable double-wall steel boxed cofferdam and on both sides of the water stoppage lock steel pipes of the side plates of the cofferdam,the crescent locks were welded so as to facilitate the inserting and extracting of the pipes and the effect of the water stoppage was quite good.

关 键 词：公路铁路两用桥 拱桥 基础施工 大直径钻孔桩 筑岛 土钉墙 栈桥 钻孔平台 钢套箱围堰 施工技术 

分 类 号：U448.22[建筑科学—桥梁与隧道工程] U445.55[交通运输工程—道路与铁道工程]