门式墩墩顶转体体系转换受力研究  

Research on Force State During Portal Pier Top Rotation

作　　者：邵志向 SHAO Zhixiang(China Railway 4th Survey and Design Group Co.,Ltd.,Wuhan 430061,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430061

出　　处：《国防交通工程与技术》2024年第4期66-69,50,共5页Traffic Engineering and Technology for National Defence

摘　　要：襄阳东西轴线跨焦柳铁路高架桥采用柔性门式墩墩顶转体施工,因转体前后体系转换受力差异问题,需要保证门式墩盖梁在体系转换前后均能满足受力要求,并在转体完成后将荷载由盖梁分摊传递至门式墩的主墩上。提出门式墩墩顶转体施工体系转换方案,采用先顶后固的方法调整球铰支撑内力,门式墩盖梁分批次张拉预应力、转体后再释放,数值模拟分析表明达到墩顶转体盖梁与主墩的协同设计目的,大幅提升了柔性门式墩结构大跨盖梁的整体力学性能。在转体施工前后,门式墩结构受力满足施工与成桥状态受力要求,盖梁应力更加均匀合理。本研究为类似桥梁项目的设计与实施提供了参考与借鉴。The Xiangyang East-West axis Overpass Project,spanning the Jiaoliu Railway,adopts the construction scheme of flexible portal pier top rotating.This scheme ensures the stability of the portal pier cap beam during system transitions and facilitates effective load transfer to the main pier.The approach involves initially adjusting the internal forces of spherical hinge supports through jacking and fixing.Subsequently,the portal pier cap beam undergoes prestressing in stages,with gradual release of prestress after rotation completion.Furthermore,through numerical simulation analysis,it has been verified that this plan can not only achieve the coordinated design of the rotating cap beam and the main pier,but also significantly enhance the overall mechanical performance of the large-span cap beam in the flexible portal pier structure.Practical validation has shown that this plan ensures the stress on the portal pier structure meets the requirements of both the construction and final bridge states throughout the entire rotation construction process,and that the stress distribution on the cap beam is more balanced and reasonable.This study serves as an important reference model and provides valuable experience for similar complex bridge projects.

关 键 词：门式墩 墩顶转体 体系转换 盖梁 预应力张拉 钢束释放 

分 类 号：U443.22[建筑科学—桥梁与隧道工程] U445.465[交通运输工程—道路与铁道工程]