48
施工技术
CONSTRUCTION TECHNOLOGY
2011年1月第40卷第2期
上海长江隧桥高桩承台围堰选型与设计
向科
（中铁二十四局集团有限公司上海
200070)
[摘要］针对长江隧桥B1标浅滩区28座高桩承台充分考虑长江口所处施工环境特点对多种围堰方案进行了技术经济分析选取了混凝土底板钢吊箱。该围堰由混凝土底板、钢吊箱壁板及内支撑、吊挂系统（下况系统）等组成壁板和底板是围堰的主要阻水结构并兼作承台模板具有施工周期短、周转材料投入少和施工风险低的特点。根据最不利工况确定了底蓝、吊挂系统和封底混凝土；采用三维有限元方法对吊箱结构的受力和变形进行了模
拟分析分析结果表明各构性应力和变形均在允许范围内[关键词】隧桥工程；混凝土底板钢吊箱；高桩承台
[中图分类号］U443.2
[文献标识码]A
[文章编号1002-8498(2011) 02-0048-04
OffshoreHigh-risePileCapFoundationCofferdam
Selection and Design of Yangtze River Crossing Project in Shanghai
Xiang Ke
( China Railway 24th Bureaa Group Co. Jad. , Shanghai 200070 ,China)
Abstract: For the constructions of 28 high-pile caps in the shallow area of the Yangtze River Crossing Project B1 section , technical and economic analysis of a variety of cofferdam programs has been carried out with full account of environmental characteristics of Yangtze River estuary. The optimal solution of concrete floor steel hanging box has been identified as a result. The cofferdam mainly consisted of four parts concrete floor , steel box hanging wall with inner support and hanging system ( sink system) . Steel wall and the floor were the main water-blocking architecture and also served as the template of the cap. Shorter period , fewer construction materials and less risk were the main characteristics of the program. Box baskets , hanging system and the back cover concrete were designed according to the most adverse conditions. Force and deformation of the hanging box structure were simulated through 3D finite element method , which showed that the stress and deformation of all components are within the allowable range. Key words: bridge and tunnel engineering; concrete floor steel hanging box; high-rise pile cap foundation
工程概况
上海长江隧桥B1标段位于长兴岛北侧其中
水中墩共28座各墩均设左右两幅承台。承台尺寸 11.7mx7.8mx2.5m承台顶标高4.0m承台底标高1.5m均为高桩承台。基础采用4根Φ1.8m钻孔灌注桩桩长77~87m（见图1）。墩身位置处水深4~12m河床变化非常明显涨、退潮时流水压力作用显著。工程地处长江口为中等强度潮汐河口。长江口季节性台风主要分布在89月的施工旺季，
对施工的影响较大。[收稿日期]2010-09-20
[作者简介】向科中铁二十四局集团有限公司上海铁建工程有限
200070电话：(021)
公司工程师上海市闵北区井和新路91号
51225527 ,E-mail: xiangke@ gmail, com 万方数据
平均高湖位不均低潮位
01.8m粘孔灌注桩
图1典型桩基础布置示意
Fig.1Typical layout of pile foundation
施工中针对滩海环境下高桩承台的特点并根据施工难度大、环境复杂、工期十分紧张等首次设计和应用了混凝土底板钢侧板组合吊箱围堰，在确