马鞍山长江公路大桥钢围堰精确定位与渡洪技术  

Techniques of Accurate Positioning and Safety of Steel Cofferdam for Maanshan Changjiang River Highway Bridge in Flood Season

作　　者：吕奖国[1] 朱瑞允[1] 吴义龙[2] 秦凤江[3] 章征[1] 

机构地区：[1]安徽省高速公路控股集团有限公司,安徽合肥230022 [2]中铁大桥局集团第四工程有限公司,江苏南京210031 [3]长安大学公路学院,陕西西安710064

出　　处：《桥梁建设》2014年第4期9-14,共6页Bridge Construction

基　　金：交通运输部建设科技项目(2013 318J14 360)~~

摘　　要：马鞍山长江公路大桥主桥为(360+1 080+1 080+360)m三塔悬索桥,该桥中塔基础为69根3.0m钻孔灌注桩,桩长80m,采用浮式吊箱钢围堰兼平台施工方案。钢围堰在工厂加工制作,采用气囊法下水,整体浮运到位,通过定位船锚碇系统与定位钢护筒,遵循先调整围堰顶面标高,后调整平面位置和扭转偏差的原则,实现了钢围堰的精确定位,平面定位精度达到了50mm。由于钢护筒插打正值长江汛期,为了在不影响施工进度的情况下保证钢围堰能够安全渡洪,通过方案比选与计算,采用插打45根钢护筒、加长21根钢护筒的渡洪技术,实现了安全渡洪。The main bridge of Maanshan Changjiang River Highway Bridge is a three tower suspension bridge with span arrangement （360＋1 080＋1 080＋360） m.The foundation for the intermediate tower of the bridge has 69 nos.of bored piles with the diameter of each pile being 3.0 m and the pile length being 80 m and the foundation was constructed by the scheme of the floatable steel boxed cofferdam that concurrently served as the working platform.The cofferdam was fabricated in the workshop,launched to the river by the air bag method and floated to the pier site in integrity.With the aid of the anchoring system of the positioning barge and the positioning steel casings in the river and on the principle of adjusting the elevation of the cofferdam top first,the plan location and torsion deviation of the cofferdam late,the cofferdam was finally accurately positioned at the pier site and the plan positioning accuracy of the cofferdam reached 50 mm.Because the time of driving the steel casings was right in the flood season of the Changjiang River,to ensure that the positioned cofferdam could be safe in the flood season on condition that the construction progress would not be hindered,after comparison and calculation,the technique of driving 45 nos.of the steel casings and lengthening 21 nos.of the casings was utilized and the safety of the cofferdam in the flood season was therefore realized.

关 键 词：悬索桥 基础工程 钢围堰 锚碇系统 钢护筒 渡洪 桥梁施工 

分 类 号：U448.25[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]