杨梅洲大桥主墩基础与桥塔施工关键技术  

Key Construction Techniques for Main Pier Foundation and Pylon of Yangmeizhou Bridge

作　　者：蔡晓男 赵辉 张文渊 CAI Xiao-nan;ZHAO Hui;ZHANG Wen-yuan(No.2 Engineering Co.,Ltd.,of CCCC Third Harbor Engineering Co.,Ltd.,Shanghai 200122,China)

机构地区：[1]中交三航局第二工程有限公司,上海200122

出　　处：《世界桥梁》2021年第2期50-56,共7页World Bridges

基　　金：中交第三航务工程局有限公司科技开发研究项目(2017-24)。

摘　　要：湘潭市杨梅洲大桥主桥为主跨658m的双塔双索面半飘浮体系斜拉桥。该桥22号、23号主墩基础均为24根Φ3m的钻孔灌注桩;桥塔为C55钢筋混凝土独柱形塔,22号塔高181m、23号塔高181.68m。该桥22号主墩采用锁口桩钢围堰施工,采用射水辅助沉桩工艺穿越平均厚8.0m的粉砂圆砾层,以加快沉桩速度;23号主墩采用重1 180t的双壁钢围堰施工,采用水上拼装工艺实现了千吨级围堰的悬浮拼装、水上浮运及原位接高,利用3组定位桩完成精确着床。主墩承台大体积混凝土施工时,从原材料选择、配合比设计、冷却水管布设、信息化监控等方面对温度进行全方位监控,以避免出现温度裂缝。主桥桥塔分节施工,塔柱外壁采用液压爬模施工、塔柱内壁及两塔肢之间采用井筒法施工;钢锚梁及钢牛腿分开吊装,利用塔壁劲性骨架实施吊装体系转换、高空组拼与精确落位。The main bridge of Yangmeizhou Bridge in Xiangtan City is a two-pylon cable-stayed bridge of a semi-floating system.The main span is 658 m long and the stay cables are fanned out in double cable planes.The foundations of piers No.22 and No.23 consist of 24 bored piles of 3 m diameter.The pylons No.22 and No.23,which are reinforced concrete mono-columns using C55 concrete,rise 181 m and 181.68 m,respectively.The main pier No.22 was constructed using interlocking steel pipe pile cofferdam,and the pipe piles were sunk through the silty clay and gravel layers with average thickness of 8 m,aided by water jetting to expedite the sinking speed.The main pier No.23 was constructed using the 1180 t double-wall steel cofferdam.The cofferdam was assembled over the river,floated and extended lift by lift at its final location,and accurately landed by using three groups of positioning piles.During the concreting of the massive pile cap of main pier,the temperature was monitored to avoid the thermal cracking,taking into account the related factors,including the raw materials,mix proportion,distribution of cooling water pipes and intelligent monitoring.The pylons were constructed section by section,with the outer walls of the pylon column concreted by hydraulic climbing formwork,and the inner walls and area between the two pylon columns constructed by shafting.The steel anchor beams and brackets were individually hoisted and installed,using the stiffening skeleton of pylon walls to realize the transformation of hoisting mode,overhead assembly and accurate lowering.

关 键 词：斜拉桥 桩基础 桥塔 锁口桩钢围堰 双壁钢围堰 大体积混凝土 液压爬模 施工技术 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U445.4[交通运输工程—道路与铁道工程]