摘要
大跨度无砟轨道铁路桥梁存在明显的工后徐变作用效应,对桥上轨道的长期线形及平顺状态产生影响。以沪苏湖高速铁路(上海—苏州—湖州)青浦特大桥为工程背景,建立大跨度连续梁-拱组合桥-CRTS双块式无砟轨道体系精细化分析模型,计算分析工后徐变作用引起的桥上无砟轨道竖向变形变化规律,并给出初步估计大跨度连续梁-拱组合桥徐变作用效应的简化计算方法。结果表明:工后徐变发生3年时,大跨度连续梁-拱组合桥上无砟轨道竖向变形已经超过了无砟轨道工后徐变10年竖向变形的50%,且中跨比边跨发展速率更快。对大跨度连续梁-拱组合桥进行徐变效应的初步计算时,可以采用折减系数为0.5的简化方法对管内混凝土徐变系数进行修正。研究结果能为考虑工后徐变的桥梁设计、运维提供了一定的理论支持。
There is a significant post construction creep effect on long-span ballastless track railway bridges,which affects the long-term alignment and smoothness of the tracks on the bridge.Taking the Qingpu extra long bridge on the Shanghai-Suzhou-Huzhou railway as the engineering background,a refined analysis model of the long-span continuous beam arch composite bridge CRTS double-block ballastless track system was established.The vertical deformation of the ballastless track on the bridge caused by post construction creep was calculated,and its variation law was studied.A simplified calculation suggestion for estimating the creep effect of the long-span continuous beam arch composite bridge was provided.The results show that after 3 years of post construction creep,the post construction creep of the vertical deformation of the ballastless track on the long-span continuous beam arch composite bridge has exceeded 50% of the 10 years post construction creep of the ballastless track,and the development rate of the mid-span is faster than that of the side span.When conducting preliminary calculations on the creep effect of long-span continuous beam arch composite bridges,a simplified method with a reduction coefficient of 0.5 can be used to correct the creep coefficient of the concrete inside the pipe.The research results provide certain theoretical support for the design and operation of bridges considering post construction creep.
作者
崔本超
于江永
刘周继
孔德芒
孙焕重
CUI Benchao;YU Jiangyong;LIU Zhouji;KONG Demang;SUN Huanzhong(China Railway 14th Bureau Second Engineering Co.Ltd.,Tai’an Shandong 271000,China)
出处
《铁道建筑》
北大核心
2023年第11期69-73,共5页
Railway Engineering
基金
中铁十四局集团公司科研课题(913700001630559891202111)。
关键词
大跨度连续梁-拱组合桥
工后徐变
数值分析
轨道竖向变形
CRTS双块式无砟轨道
long-span continuous beam-arch composite bridge
post construction creep
numerical analysis
vertical deformation of track
CRTS double-block ballastless track
