市域铁路大跨连续梁桥上无缝道岔群纵向力学特性分析  

Analysis of Longitudinal Mechanical Properties of Continuously Welded Rail Turnout Groups on Long-span Continuous Girder Bridge of Suburban Railways

作　　者：张艳平 ZHANG Yanping(Dongguan Rail Transit Co.,Ltd.,Dongguan 523076,China)

机构地区：[1]东莞市轨道交通有限公司,广东东莞523076

出　　处：《高速铁路技术》2022年第4期40-46,共7页High Speed Railway Technology

摘　　要：文章以某市域铁路高架站后咽喉区(40+64+40) m四线变双线道岔梁+26 m简支梁+6×32 m单渡线道岔梁为工程背景,基于岔-桥相互作用原理和非线性有限单元法,建立岔-桥-墩一体化计算模型,分析不同轨道设计方案下大跨连续梁桥上无缝道岔群纵向力变化规律,并以规范要求开展设计检算,结果表明:(1)钢轨伸缩力、制动力峰值均出现在大跨连续梁右梁缝处;(2)全桥采用常阻力扣件时,钢轨伸缩力最大值达到965.1 kN,钢轨总应力超过容许应力限值;(3)采用小阻力扣件可大幅降低钢轨伸缩力,对钢轨制动力则影响不大;(4)铺设小阻力扣件、适当降低锁定轨温、放大断缝值要求等轨道措施可使得无缝道岔应力、位移指标满足设计要求。研究结果可为大跨连续梁桥上无缝道岔群轨道设计方案提供参考。Taking the(40+64+40) m four-track to double-track turnout girder +26 m simply supported girder +6×32 m single crossing turnout girder in the back throat area of a suburban railway elevated station as the case for analysis, the integrated calculation model of turnout-bridge-pier is established based on the principle of turnout-bridge interaction and nonlinear finite element method, to analyze the variation law of longitudinal force of continuously welded turnout groups on long-span continuous girder bridges under different track design schemes, and the design is carried out according to the specification requirements. The results show that:(1) The peak values of rail stretching force and braking force appear at the right girder joint of long-span continuous girder.(2) When constant resistance fasteners are used for the whole bridge, the maximum rail stretching force reaches 965.1 kN, and the total rail stress exceeds the allowable stress limit.(3) Using small resistance fastener can greatly reduce rail stretching force, but has little effect on rail braking force.(4) Track measures such as laying small resistance fasteners, appropriately reducing the locked rail temperature, and enlarging the requirement of broken seam value can make the stress and displacement indexes of continuously welded rail turnout meet the design requirements. The research results can provide a reference for the track design scheme of continuously welded rail turnout group on long-span continuous girder bridges.

关 键 词：市域铁路 桥上无缝道岔 数值模拟 钢轨纵向力 轨道力学检算 小阻力扣件 

分 类 号：U213.6[交通运输工程—道路与铁道工程]