摘要
厦漳跨海大桥北汊主桥为主跨780m的钢箱梁斜拉桥,桥塔位于海上浅滩区域。经过多方案比选,桥塔墩顶区钢箱梁采用活动托架辅助不变幅架梁吊机架设。活动托架的核心结构——活动三角托架由走道梁、斜撑、横撑、立柱和升降系统等组成,通过附着于立柱上的升降系统上下移动,带动斜撑下端在竖向滑道上移动,实现走道梁水平与竖向位置的变位,通过走道梁的竖向和水平向的变位为钢箱梁提升时留出上升空间,横移时提供支承。为优化托架受力、解决现场拼装精度难题,提出2个优化结构受力技术措施、2个活动三角托架安装精度措施、2个三角托架活动机构变位效率和可靠性技术措施。结构计算表明活动托架结构受力满足规范要求。
The north main bridge of the Xiazhang Sea-crossing Bridge is a steel box girder cable-stayed bridge with a main span of 780 m.The pylons of the bridge are located in the offshore shallow water areas.It was determined through scheme comparison and selection that the steel box girder segments over the pylon pier tops could be erected using constant-range gantry crane assisted by movable supporting frames.The key components of the movable supporting frame are the movable triangular brackets comprising the access beam,diagonals,the lateral bracing,posts and lifting system.The movable brackets can be lifted up and down by the lifting system attached to the posts,allowing the lower part of the diagonals to move on the vertical slides,in turn,to realize the shifts of the horizontal location and vertical location of the access beam,leaving vertical clearance for the lifting-up of the steel box girder and providing support during the transverse moving of the steel box girders.In the structural design process,the load bearing mechanism was optimized to ensure the installation precision of the movable triangular brackets,so as to improve the location-shift efficiency and reliability of the triangular brackets.In the optimization process,the problems that exist in the load bearing mechanism of the brackets and the field assembling accuracy are solved.The structural calculation indicates that the load bearing performance of the movable brackets meet the code requirements.
出处
《世界桥梁》
北大核心
2016年第2期1-6,共6页
World Bridges
关键词
斜拉桥
钢箱梁
桥梁架设
活动托架
活动三角托架
不变幅架梁吊机
托架结构设计
cable-stayed bridge
steel box girder
bridge erection
movable frame
movable triangular brackets
constant-range gantry crane
bracket structure design
作者简介
叶绍其（1977-），男，高级工程师，2001年毕业于武汉化工学院交通土建工程专业，工学学士（E—mail：yeshaoqi@yeah．net）。
