扬州万福大桥主梁体系转换研究  

Research of System Transformation of Main Girder of Wanfu Bridge in Yangzhou

作　　者：叶庆旱[1] 肖颉 覃勇刚[1] 

机构地区：[1]中铁大桥局集团有限公司,湖北武汉430050

出　　处：《桥梁建设》2016年第3期57-62,共6页Bridge Construction

摘　　要：扬州万福大桥主桥为(94+188+94)m的混凝土自锚式悬索桥。结合该桥后期荷载大、体系非线性强、工期紧张等特点,对主梁体系转换过程中的吊杆安装顺序、主梁压重以及支承条件影响进行研究,最终确定主梁体系转换方案。考虑吊杆受力及有利于后期方案的优化,吊杆采取从塔根向跨中的顺序张拉;为消除主梁下缘受力不利的影响、避免混凝土开裂,在张拉吊杆过程中,采取在主梁相应位置施加与二期恒载及下层桥面荷载等重的压重荷载;由于主梁现浇支架的刚度对其受力影响较小,支架设置为相同刚度。实施效果表明,主梁体系转换成功,线形和内力符合规范和设计要求,所采用的方案减少了吊杆张拉轮次,具有操作方便、控制简单、工期短的优点。The main bridge of the Wanfu Bridge in Yangzhou is a concrete self-anchored suspension bridge with span arrangement（94＋188＋94）m.In the light of the characteristics that the later time load of the bridge was heavy,the system nonlinearity was prominent and the construction time schedule was tight,the influences of the suspender installation sequences and the ballast load and support conditions of the main girder of the bridge in the system transformation of the girder were researched and the scheme of the system transformation was accordingly determined.Considering the forces of the suspenders and the favor of the later time optimization of the bridge,it was specifically determined that the suspenders should be tensioned in a sequence from the towers towards the midspan.To eliminate the influences of the unfavorable forces of the main girder lower edges and to avoid the cracking of the concrete,in the tensioning of the suspenders,the measures of applying the ballast load that had the equal weight to the second phase dead load and lower deck load to the corresponding positions of the girder were taken.Since the influences of the stiffness of the cast-in-situ scaffoldings for the main girder on the forces of the scaffoldings were little,the scaffoldings were arranged in a way of the same stiffness.The results of the field implementation of the system transformation scheme proves that the system transformation of the main girder is successful and the geometric shapes and internal forces of the girder conform to the requirements in the codes and design.The scheme can reduce the tensioning times of the suspenders and has the advantages of easy operation,simple control and short construction time schedule.

关 键 词：自锚式悬索桥 混凝土主梁 体系转换 吊杆 安装顺序 压重 支承条件 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U443.35[交通运输工程—道路与铁道工程]