摘要
为研究大跨度铁路刚构-连续组合体系梁桥钢-混结合段的力学性能,以新建杭温铁路永嘉右行线跨甬台温特大桥主桥为背景,基于原桥节段有限元模型研究钢-混结合段的应力分布及传力特性,并基于缩尺模型试验对钢-混结合段承载能力、变形性能等进行分析。结果表明:刚构-连续组合体系梁桥钢-混结合段传力较为顺畅,钢-混结合段钢结构、混凝土结构纵向应力横向分布不均匀系数分别为0.72~1.42、0.63~1.31,钢-混结合段内纵向应力横向分布不均匀现象较过渡段更为显著;后承压板在传力过程中起着重要作用,结合段通过后承压板、剪力钉及PBL连接件分别可传递约56.4%、27.4%、16.2%的轴力,钢-混结合段中1.5 m钢格室段及2.5 m伸长段中钢结构分别将28.3%、15.3%的轴力传递给混凝土;结合段在1.8 P(P为设计荷载)作用下仍处于弹性工作状态,具有足够的承载能力,钢、混凝土强度安全系数分别不小于2.7、2.4;钢-混结合段挠度与三次多项式相符较好,变形较为平顺。
The river-crossing main bridge of a bridge crossing the Ningbo-Taizhou-Wenzhou Railway and carrying part of the right line of Yongjia section of the newly-built Hangzhou-Wenzhou Railway is used as a case to study the mechanical property of the steel-concrete joint section of the long-span combined rigid frame and continuous girder railway bridge.A finite element sectional model was built up to study the stress distribution and load transfer characteristics of the steel-concrete joint section.Scaled-down model test was conducted to analyze the load bearing and deformation behaviors of the steel-concrete joint section.It is shown that the steel-concrete joint section of the combined rigid frame and continuous girder bridge transfers loads smoothly,the transverse distribution non-uniform coefficients of the longitudinal stresses in the steel and concrete components of the steel-concrete joint section are 0.72 to 1.42 and 0.63 to 1.31,respectively.The non-uniform transverse distribution of the longitudinal stresses in the steel-concrete joint section is more significant than the transition section.The rear bearing plate plays an important load transferring role.The rear bearing plate,shear studs and PBL connectors share correspondingly 56.4%,27.4%and 16.2%of the axial forces.The steel constituents in the 1.5 m-long steel chamber and 2.5 m-long flanged section transfer 28.3%and 15.3% of axial forces to the concrete.The steel-concrete joint section still remains in elastic working condition under 1.8 P(P refers to design load)and has sufficient load bearing capacity,with safety factors of the steel and concrete strengths no less than 2.7 and 2.4,respectively.The deflection of the steel-concrete joint section agrees well with the solution of the trinomial,indicating smooth deforming behavior.
作者
茅为中
蒲黔辉
杨仕力
洪彧
杨朝龙
MAO Weizhong;PU Qianhui;YANG Shili;HONG Yu;YANG Chaolong(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;School of Architecture and Civil Engineering,Chengdu University,Chengdu 610106,China;China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430063,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2023年第5期41-49,共9页
Bridge Construction
基金
广西省科技计划项目(桂科AA21077011)
四川省科技计划资助项目(2021YJ0054)。
关键词
铁路桥
刚构-连续组合体系梁桥
钢-混结合段
应力分布
变形性能
有限元法
模型试验
railway bridge
combined rigid-frame and continuous girder bridge
steel-concrete joint section
stress distribution
deformation performance
finite element method
model test
