单元化后高速铁路桥上CRTSⅡ型板式无砟轨道结构纵向力分布规律研究  

Research on Longitudinal Force Distribution of Unitized CRTSⅡ Slab Ballastless Track on Bridge

作　　者：蔡嘉升 陈进杰 王建西[1,3] 陈龙 李杨[4] 薛志强 CAI Jiasheng;CHEN Jinjie;WANG Jianxi;CHEN Long;LI Yang;XUE Zhiqiang(School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Hebei Key Laboratory of Geotechnical Engineering Safety and Deformation Control,Cangzhou 061001,China;State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao University,Shijiazhuang 050043,China;School of Traffic and Transportation,Shijiazhuang Tiedao University,Shijiazhuang 050043,China)

机构地区：[1]石家庄铁道大学土木工程学院,石家庄050043 [2]河北省岩土工程安全与变形控制重点实验室,河北沧州061001 [3]石家庄铁道大学交通工程结构力学行为与系统安全国家重点实验室,石家庄050043 [4]石家庄铁道大学交通运输学院,石家庄050043

出　　处：《铁道标准设计》2021年第9期45-51,共7页Railway Standard Design

基　　金：河北省研究生创新资助项目(CXZZSS2020066);河北省自然科学基金项目(E2019210264;E2020210092);河北省高校百名优秀创新人才支持计划(SLRC2019036);京沪高速铁路股份有限公司科研计划课题(P2018G005)。

摘　　要：针对我国高速铁路CRTSⅡ型板式无砟轨道胀板、离缝等病害问题,按照四块板的单元化方案对CRTSⅡ型板式无砟轨道进行单元化处理,建立多跨简支梁桥无缝线路桥梁-轨道耦合模型,研究桥上CRTSⅡ型板式无砟轨道结构纵向力分布规律,分析不同弹性模量的宽窄接缝对钢轨纵向力、钢轨位移、轨道板纵向应力及桥梁纵向位移的影响。研究结果表明:(1)当弱连接处弹性模量取15500MPa时,无砟轨道结构整体受力减小,钢轨纵向力、钢轨纵向位移及轨道板纵向应力出现应力、位移突变现象,突变幅值在安全范围之内;(2)单元化时需关注弱连接位置、梁缝处钢轨受力及钢轨的爬行,防止钢轨力变化幅度过大导致钢轨疲劳断裂,在弱连接位置发生较大变形;(3)单元化时,弱连接处填充材料的弹性模量是影响CRTSⅡ型板式无砟轨道结构受力的关键因素;(4)单元化对桥梁整体纵向位移的影响很小,可忽略不计。In view of the problems such as expansion and separation of the CRTSⅡ slab ballastless track in China's high-speed railways,this paper establishes a unitized multi-span simply supported beam seamless track bridge-track coupling model according to the four-plate unitization plan to unitize the CRTSⅡ slab ballastless track,studies the longitudinal force distribution of the track structure after the CRTSⅡ slab ballastless track is unitized on the bridge,and analyzes the longitudinal force of the rail,the rail displacement,the longitudinal stress of the slab and the longitudinal displacement of the bridge under the influence of the wide and narrow joints with different elastic moduli.The research results show that:(1)When the elastic modulus of the weak connection is 15500MPa,the unitization of CRTSⅡ slab ballastless track can reduce the longitudinal stress of the track slab;the rail force,rail displacement,and longitudinal stress of the track slab are subject to stress and displacement mutation,but the mutation is within the safety range;(2)During unitizing,more attention should be paid to the change of rail displacement at the weak connection and the crawling of the rail to prevent the rail from excessive change,which may cause rail fatigue fracture and large displacement and deformation at the weak connection;(3)After unitization,the value of the elastic modulus of the filling material at the weak connection is the key factor affecting the stress of the CRTSⅡ slab ballastless track structure;(4)The influence of unitization on the overall longitudinal displacement of the bridge is very small and can be ignored.

关 键 词：高速铁路 桥梁-轨道耦合模型 CRTSⅡ型板式无砟轨道 单元化 无缝线路 

分 类 号：U213.244[交通运输工程—道路与铁道工程]