强涌潮地区桥梁防撞钢套箱支腿病害修复技术  

Techniques to Repair Damage and Lost Part of Legs of Anti-collision Steel Box for Bridge in Strong Tidal Current Area

作　　者：郭勇 GUO Yong(Zhejiang Jiashao Kuajiang Bridge Investment Development Co.,Ltd.,Shaoxing 312366,China)

机构地区：[1]浙江嘉绍跨江大桥投资发展有限公司

出　　处：《世界桥梁》2019年第6期80-84,共5页World Bridges

摘　　要：嘉绍大桥位于钱塘江尖山河段,在主副航道桥桥墩底部安装防撞钢套箱,每个钢套箱下设10~16根支腿,支腿与主体结构栓接。受强涌潮的冲刷作用,部分钢套箱支腿偏移甚至缺失,造成钢套箱失稳并降低了防撞击能力。修复施工时,利用现有墩顶平台、钢套箱检修平台、桥面栏杆等搭设作业通道;采用吊篮、笼梯、手拉葫芦、简易吊机等轻质简易设备;取消支腿栓接构造及支腿与承台间的橡胶垫块,增加连接加劲板将支腿与钢套箱底部焊接固定,支腿直接支撑在承台上;采用多套手拉葫芦牵引拖拽纠偏支腿,按先校正再焊接的方式完成偏移支腿的修复;针对缺失的支腿,按原设计制作新支腿(长度增加500mm),分2段制作安装、现场焊接成整体,与钢套箱底板开孔形成轴套配合构造,以增加受力性能。The Jiashao Bridge is located at the Jianshan Section of Qiantang River. The piers of themain and subsidiary shipping channel bridges are protected by anti-collision steel boxes at the base, and each steel box has 10 to 16 legs that are bolted with themain body of the box. Due to the scour action of strong tides and currents, the legs of some steel boxes displaced or got lost, which undermined the stability and anti-collision capacity of the steel boxes. During the remedial construction process, the existing pier-top platforms, the repairing platform of the steel box and handrails on the bridge were relied to install the working passages, and the light and simple equipment, like hanging basket, cage ladder, winches and simple crane, were deployed. The bolted connection of the legs to themain body of the steel box and the rubber padding blocks between the legs and the pile caps were removed, stiffening plates were added to allow the legs to be welded and fixed to the base of the steel boxes, and the legs were shifted to directly support on the pile caps. Multiple sets of winches were used to tow and drag the legs to rectify their displacement, and the displaced legs were first adjusted and then welded for remedial. For the lost legs, new legs were prepared simulating the original design, but 500mm longer than the old ones. The new legs were divided into two sections to facilitate fabrication and assembly, and welded to be a whole in the field, which can form an axle-sheath collaborated structure with the holes on the base of the steel box to enhance their load bearing capacity.

关 键 词：嘉绍大桥 强涌潮 钢套箱 支腿 偏移 缺失 修复技术 

分 类 号：U443.26[建筑科学—桥梁与隧道工程] U445.71[交通运输工程—道路与铁道工程]