温差和列车荷载作用下中低速磁浮轨道结构变形分析

Deformation analysis of medium-low speed magnetic levitation track structure under temperature difference and train load action

中低速磁浮轨道F型导轨的变形直接影响列车运行安全性与舒适性,是磁浮交通线下结构设计需要研究的问题。结合国内某中低速磁浮试验线工程,建立了包括轨排、高架梁及其联结件的磁浮轨道结构有限元模型,计算分析温差和列车荷载作用下导轨竖向与纵向位移响应。结果表明：在温差荷载作用下导轨竖向变形呈上拱抛物线形,最大上挠量为5.1 mm,跨中和梁端轨缝伸缩量为-4.7~0.3 mm;在温差和列车荷载共同作用下导轨上拱明显减小,某些工况下导轨近似回落至水平状或呈下挠变形,最大下挠量为2.51 mm,跨中和梁端轨缝伸缩量在-4.6~3.8 mm。

The geometrical deformation of the F-type guide rails in the low-medium speed magnetic levitation track directly influences train operation safety and ride comfort,which is an issue need to be studied of the structure design in the magnetic levitation transportation line. Based on a low-medium speed magnetic levitation test line engineering in China,a finite element model of magnetic levitation track structure including the track panel,the girder and its connection components was established,and the vertical and longitudinal displacement responses of the guide rails were calculated under temperature difference and train load. Test results showed that the vertical deformation of guide rails under temperature difference loads appears upwarp parabola,the maximum upwarp amount is 5. 1 mm,the expansion amount of the rail gap on the beam end and the mid-span ranges from- 4. 7 mm to 0. 3 mm,the upwarp amount of the guide rails decreased evidently under the temperature difference and train loads,the guide rails will retreat approximately to a horizontal plane or have down-warping deformation under certain load conditions,the maximum down-warping amount is 2. 51 mm,and the expansion amount of the rail gap on the beam end and the mid-span is from- 4. 6 mm to3. 8 mm.