高速铁路64 m简支箱梁桥上无砟轨道无缝线路纵向力分析与桥墩刚度限值研究  

Research on the Limit Value of Pier Longitudinal Stiffness and Rail Longitudinal Force Analysis of 64 m Simply Supported Box Beam Bridge with Ballastless Track

作　　者：王伟华 WANG Weihua(China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]中国铁路设计集团有限公司,天津300308

出　　处：《铁道标准设计》2021年第6期82-88,共7页Railway Standard Design

基　　金：中国铁路设计集团有限公司科技开发课题(7218120);中国科协青年人才托举工程(2018QNRC001)。

摘　　要：为探究桥梁与轨道参数对无缝线路纵向受力变形的影响,建立跨度64 m简支梁桥上CRTSⅢ型无砟轨道无缝线路空间耦合有限元模型,分析复杂荷载下扣件阻力、弹性缓冲垫层及桥墩纵向刚度等参数对无缝线路的影响。研究结果表明:小阻力扣件可减小钢轨纵向力、缓冲凹槽和凸台间的相互作用,但会增加梁-轨相对位移,无砟轨道64 m简支梁桥上铺设常阻力扣件时轨道结构的安全性也能满足要求;增大弹性缓冲垫层刚度会显著增加凸台纵向力;增大桥墩纵向刚度会增加钢轨伸缩力,减小制动荷载作用下的钢轨纵向力、梁-轨相对位移及凸台纵向力。建议无砟轨道限位凹槽侧面应优先设置高弹缓冲垫层,以减小凸台纵向力;64 m跨度CRTSⅢ型无砟轨道简支梁桥上铺设常阻力扣件,钢轨温差分别取30、40、50℃时,其桥墩纵向刚度限值分别为440、440、700 kN/cm。In order to explore the influence of bridge and track parameters on the longitudinal deformation of CWR,the spatial coupling model of CRTSⅢballastless CWR track on 64m simply supported beam bridge is established with finite element method to analyze the effects of fastener resistance,elastic modulus of rubber pad and longitudinal stiffness of piers on the CWR track.The research results show that small resistance fasteners can reduce the longitudinal force of rail and buffer the interaction between groove and concrete convexity while the beam-rail relative displacement increases,and the safety of track can also meet the requirements with constant resistance fasteners in place.The increment of the elastic modulus of rubber pad raises the longitudinal force of concrete convexity.Improving the longitudinal stiffness of pier leads to the increase of the expansion force under temperature load,and results in the decrease of the beam-rail relative displacement and longitudinal force of concrete convexity under braking load.The high-elastic rubber pads are suggested to be installed around the positive stop groove to reduce the longitudinal force of concrete convexity.When constant resistance fasteners are laid at the assigned rail temperature of 30℃,40℃and 50℃,the pier longitudinal stiffness limit values are 440 kN/cm,440kN/cm and 700 kN/cm respectively.

关 键 词：铁路桥 简支梁桥 无砟轨道 无缝线路 纵向力 弹性缓冲垫层 桥墩纵向刚度 高速铁路 

分 类 号：U213.21[交通运输工程—道路与铁道工程] U441.7[建筑科学—桥梁与隧道工程]