高速铁路大跨度刚构部分斜拉桥设计关键技术  

Key Design Techniques of High Speed Railway Long⁃span Rigid Frame Extradosed Bridge

作　　者：张欣欣[1] ZHANG Xinxin(China Railway Shanghai Design Institute Group Co.,Ltd,Shanghai 200070,China)

机构地区：[1]中铁上海设计院集团有限公司,上海200070

出　　处：《铁道建筑》2023年第9期54-58,共5页Railway Engineering

基　　金：中国国家铁路集团有限公司科技研究开发计划(N2022G065)。

摘　　要：预应力混凝土部分斜拉桥结构刚度大,经济性好,适宜铺设无砟轨道,是200~300 m跨度高速铁路桥梁的首选桥型。本文以高速铁路主跨248 m刚构部分斜拉桥为背景,研究高速铁路大跨度刚构部分斜拉桥合理的结构体系、轨道平顺性、索梁荷载比、合龙顶推力等关键技术。静力计算结果表明:刚构体系比连续梁体系刚度更大,经济性好,更有利于行车安全性;两种结构体系轨道不平顺均能满足要求,对于长短波不平顺,与连续梁体系相比刚构体系中跨不平顺值小,边跨不平顺值大;索梁荷载比与斜拉索刚度成正比,与主梁刚度成反比;刚构部分斜拉桥合龙后的收缩徐变和高温合龙导致结构产生附加内力,合理设置顶推力须综合考虑主墩受力与运营阶段塔顶位移。The prestressed concrete extradosed bridge has large structural stiffness,good economy,and is suitable for ballastless track.It is the preferred bridge type for 200~300 m span high speed railway bridges.Taking the high speed railway main span 248 m rigid frame partial cable-stayed bridge as the background,the reasonable structural system,track smoothness,cable-girder load ratio,closure top thrust and other key technologies of the high speed railway longspan rigid frame extradosed bridge were studied.The static calculation results indicate that the rigid frame system has greater stiffness,better economy,and is more conducive to driving safety than the continuous girder system.Both types of structural systems can meet the requirements for track irregularities.For long and short wave irregularities,compared to continuous girder systems,rigid frame systems have lower mid-span irregularities and higher side-span irregularities.The cable-girder load ratio is directly proportional to the stiffness of the cable and inversely proportional to the stiffness of the main girder.The shrinkage,creep,and high temperature closure of the rigid frame extradosed bridge after closure can lead to additional internal forces in the structure.Reasonable setting of the jacking force requires comprehensive consideration of the main pier stress and tower top displacement during operation.

关 键 词：高速铁路桥梁 部分斜拉桥 理论计算 结构体系 轨道不平顺 索梁荷载比 顶推力 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]