双固定墩对市域铁路桥上无缝线路纵向力的影响研究  

The influence of Double Fixed Piers on the Longitudinal Mechanical Characteristics of Continuous Welded Rail on Bridges of the Suburban Railway

作　　者：梁爽 刘德志[1] 王小韬[1] 周华龙[1] LIANG Shuang;LIU Dezhi;WANG Xiaotao;ZHOU Hualong(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道标准设计》2023年第6期20-26,共7页Railway Standard Design

基　　金：中铁二院工程集团有限责任公司科研课题(KSNQ203030)。

摘　　要：针对双固定墩对桥上无缝线路纵向力的影响开展研究,以某市域铁路为实际工程背景,基于梁轨相互作用原理、非线性有限单元法,建立线-桥-墩一体化计算模型,分析温度变化、列车制(启)动以及断轨工况下双固定墩简支梁桥上无缝线路纵向力变化规律,并以规范要求进行轨道力学检算。计算结果表明,相比普通桥上无缝线路而言,双固定墩对钢轨最大伸缩及制动拉力影响不大,但显著提高伸缩压力的峰值;双固定墩所受纵向力近似为0,但与双固定墩相邻桥墩承受的纵向力增幅达到50%左右;当钢轨在双固定墩处折断时,双固定墩对钢轨断缝有抑制作用;从桥上无缝线路受力角度考虑,当墩刚度低于500 kN/(cm·单线)时,双固定墩桥上无缝线路无需单独进行轨道力学检算,桥梁专业按规范取值进行桥墩检算即可满足工程设计需求。研究结果可为双固定墩桥上无缝线路轨道系统和墩台设计提供参考。The influence of double fixed piers on the longitudinal force of continuously welded rail(CWR)on bridge is studied.Taking a Municipal Railway as the actual engineering background,the integrated calculation model of line bridge pier is established based on the principle of beam rail interaction and nonlinear finite element method to analyze the variation law of the longitudinal force of CWR on the simply supported beam bridge with double fixed piers under the conditions of temperature change,train braking(starting)and track breaking.The calculation results show that,compared with CWR on ordinary bridge,double fixed piers have little effect on the maximum expansion and braking tension of rail,but significantly increase the peak value of expansion pressure.The longitudinal force on the double fixed pier is approximately 0,but the longitudinal force on the pier adjacent to the double fixed pier increases by about 50%.When the rail is broken at the double fixed pier,the double fixed pier can inhibit the rail fracture.Considering the stress of the CWR on the bridge,when the pier stiffness is less than 500 kN/cm per single line,the CWR on the double fixed pier bridge does not need to be checked and calculated separately for track mechanics,and the bridge professional can meet the engineering design requirements by taking the value of the pier according to the specifications.The research results can provide reference for the design of CWR track system and pier and abutment on double fixed pier bridge.

关 键 词：无缝线路 双固定墩 梁轨相互作用 轨道力学检算 市域铁路 

分 类 号：U213.9[交通运输工程—道路与铁道工程] U239.5