高铁混合梁斜拉桥钢-混结合段构造优化研究
Study on Structural Optimization of Steel-Concrete Joint of High-Speed Railway Composite Girder Cable-Stayed Bridge
何知明 1李英铭 2张莹 2施洲2
作者信息
- 1. 汉巴南城际铁路有限责任公司,四川巴中 636099
- 2. 西南交通大学土木工程学院,成都 610031
- 折叠
摘要
为优化高速铁路混合梁钢-混结合段构造,使其便于施工且受力合理,依托主跨335 m的汉巴南铁路嘉陵江大桥开展结合段构造优化研究.将原结合段前承压板及钢格室优化为钢锚室并缩短钢混黏结段长度,提出优化构造方案;基于有限元仿真分析,研究结合段结构优化前后应力分布规律和传力特性.结果表明:优化前后钢-混结合段在最大正、负弯矩工况下应力沿纵向分布规律基本相似,原结合段前承压板传力作用并不显著;除部分应力集中点外,优化前后结合段应力差异并不显著,均小于17％.两种工况下,优化前后钢-混结合段均以承压板的直接承压为主要传力路径(R1),传递62.72％～66.65％钢梁轴力至混凝土;原结合段顶底板及腹板通过剪力钉传力(R2)、PBL钢板及PBL剪力键传力(R3)分别传递19.79％/22.54％、13.56％/12.68％的钢梁轴力,传力相对均匀;优化后结合段通过R3路径仅传递6％左右钢梁轴力至混凝土,R2路径传力比显著高于R3路径.优化后结合段在保证合理受力的条件下缩减了结合段的长度,有效降低施工难度.
Abstract
To optimize the structure of the hybrid girder steel-concrete composite joint of high-speed railway bridges for improved constructability and reasonable stress distribution,this study investigated structural optimization of composite joint based on the 335-meter main span Jialing River Bridge on Hanzhong-Bazhong-Nanchong High-speed Railway.The optimized structure scheme was proposed by replacing the front bearing plate and steel girder chamber of the original joint with a steel anchor chamber.The length of the steel-concrete bonding composite joint was also reduced.Based on finite element simulation analysis,the stress distribution patterns and force transfer characteristics before and after the optimization of the joint were studied.The results showed that the stress distribution along the longitudinal direction of the steel-concrete joint before and after optimization was generally similar under maximum positive and negative bending moment conditions,and the force transfer effect of the front bearing plate of the original joint was not significant.Except for some stress concentration points,the stress differences before and after optimization were not significant,with all differences being less than 17％.Under the two working conditions,the steel-concrete joint before and after optimization mainly transferred the axial force of the steel beam to the concrete through the direct bearing of the bearing plate(R1),accounting for 62.72％to 66.65％.In the original joint,the top and bottom plates and web plates transferred the axial force of the steel beam to the concrete through shear studs(R2),PBL steel plates,and PBL shear keys(R3),respectively,transmitting 19.79％/22.54％and 13.56％/12.68％of the steel beam axial force,ensuring relatively uniform force transfer.After optimization,the joint transferred only about 6％of the steel beam axial force to the concrete through the R3 path,and the force transfer ratio through the R2 path was significantly higher than that of the R3 path.The length of the optimized joint was reduced while ensuring reasonable stress distribution,effectively reducing the construction difficulty.
关键词
铁路桥/混合梁斜拉桥/钢-混结合段/构造优化/有限元分析/受力特性/传力比Key words
railway bridge/hybrid girder cable-stayed bridge/steel-concrete composite joint/structural optimization/finite element analysis/stress characteristics/force transfer ratio引用本文复制引用
出版年
2025
NETL
NSTL
万方数据