摘要
兰州中山桥为1909年建成的5跨简支铆接钢桁梁桥,属于全国重点文物保护建筑。为满足现有规范对桥梁的正常使用要求并综合考虑文物保护的要求,决定将该桥提升1.2m。结合改造前对该桥工程状况的评估制定提升基本原则,并进行桥梁提升方案比选,最终决定采用计算机同步控制提升技术及合点提升技术对钢桁梁进行整体提升。采用MIDAS Civil建立5跨钢桁梁整体模型及桥墩(台)提升支架模型,进行提升安全评价,计算结果表明:提升结构满足使用要求。提升系统由提升支架、吊点构造、提升设备及辅助设施组成。采用具有自回复力的12束柔性钢绞线对钢桁梁进行整体同步提升,提升按60级进行,每级20mm,采用限位装置及支撑钢垫盒进行实时限位保护,对提升的稳定性和同步性进行控制,实现每级提升高差控制在2mm以内。
The Zhongshan Bridge in Lanzhou City is a five-span simply-supported riveted steel truss girder bridge, completed in 1909. The bridge now is one of the cultural relics under state protection in China. In order to make the bridge meet the operation requirement of the current specification, in view of the demands of protection of historical relics, it is determined that the bridge be raised 1.2 m. Combined with the evaluation of the condition of the bridge before reno- vation, the basic raising principle was determined and the scheme comparison and selection were also carried out. A scheme of using computer synchronous control raising technique and the cha- laza raising technique was taken for the raising of the steel truss girder monolithically. The MI- DAS Civil software was used to set up the overall model of the five-span steel truss girder and the raising scaffolding model of the bridge piers to carry out the safety evaluation of the raising. The result of the calculation shows that the structure after raising renovation meets the operation re- quirement. The raising system was formed of raising scaffolding, raising point composition, rai- sing equipment and auxiliary equipment. The 12 flexible steel strands with resilient ability were adopted to do the monolithic and synchronous raising of the steel truss girder. The raising process included 60 grades each 20 mm. The position limitation device and the supporting steel cushion box were used to do real-time position limitation protection and to control the stability and synchronicity of the raising operation, realizing the goal that the height difference of the raising of each grade was controlled within 2 mm.
出处
《世界桥梁》
北大核心
2012年第6期80-86,共7页
World Bridges
基金
中交二航局"兰州中山桥维修加固成套技术研究"基金资助项目
关键词
简支钢桁梁桥
桥梁改建
整体提升
计算机同步控制技术
合点提升技术
, simply-supported steel truss girder bridge
bridge renovation
monolithic raising
computer synchronous control technique
chalaza raising technique
