齿条无缝化对简支梁桥上无缝线路的影响研究

Research on the Influence of Seamless Rack on the Continuous Welded Rail on the Simply Supported Girder Bridge

研究目的:齿轨铁路具有良好的爬坡能力,成为山地铁路的主要形式。为研究齿条无缝化对齿轨铁路简支梁桥上无缝线路的影响规律,基于梁轨相互作用原理和桥上齿轨铁路线路特点,建立考虑无缝齿条的钢轨(齿轨)-轨枕-桥梁-墩台一体化计算模型,研究伸缩、制动、挠曲及断轨工况下齿条无缝化对桥上无缝线路钢轨纵向力、变形及墩台力的影响规律。研究结论:(1)与传统桥上无缝线路相比,齿条无缝化主要影响钢轨制动力和断缝值;(2)随着线路坡度增大,伸缩、挠曲和断轨工况下钢轨纵向力、桥墩纵向力、钢轨断缝值均减小,制动工况下钢轨制动力、桥墩纵向力和梁轨相对位移均增大;(3)当线路坡度增大至480‰时,钢轨伸缩力、齿条伸缩力和墩台力均减小,钢轨和齿条的伸缩力减小了4.24%,桥墩墩台力减小了4.17%;钢轨挠曲力、齿轨挠曲力、桥梁墩台力均减小,钢轨挠曲力、齿轨挠曲力和桥梁墩台纵向力分别降低15.07%、12.77%和11.18%;钢轨制动力、齿条制动力、桥墩纵向力、钢轨桥梁相对位移、齿条桥梁相对位移均增大,分别增大了3.12倍、4.37倍、3.51倍、3.33倍和4.60倍,需要防止齿轨铁路纵向失稳;钢轨断缝值增大了3.44%,墩台纵向力减小了4.60%;(4)相关研究成果可为桥上齿轨铁路无缝化设计提供参考。

Research purposes:The rack railway has good climbing ability and has become the main type of mountain railway.In order to study the influence of seamless rack on the continuous welded rail(CWR)on the simply supported girder bridge of the rack railway,a rail(rack)-sleeper-bridge-pier integration model was established based on the bridge-track interaction and the characteristics of rack railway on bridges.The influence law of the seamless rack on the longitudinal force and deformation of the CWR on the bridge and the pier force is obtained.Research conclusions:(1)The seamless rack mainly affects the rail braking force and rail gap compared with the traditional CWR on the bridge.(2)With the increase of the gradient of the railway,the rail longitudinal force,the bridge pier longitudinal force,and the rail gap all decrease under the expansion,deflection and rail breaking conditions,the rail braking force,bridge pier longitudinal force and relative displacement between bridge and rail all increase under the braking condition.(3)When the railway gradient increases to 480‰,the rail expansion force,rack expansion force and abutment force decrease,the expansion force of rail and rack decreases by 4.24%,and the bridge pier abutment force decreases by 4.17%.The rail deflection force,the rack deflection force and the abutment force all decrease,the rail deflection force,the rack deflection force and the abutment longitudinal force decrease by 15.07%,12.77%and 11.18%respectively.The rail braking force,the rack braking force,the longitudinal force of the bridge pier,the relative displacement of the rail bridge and the relative displacement of the rack bridge increase by 3.12 times,4.37 times,3.51 times,3.33 times and 4.60 times respectively.As for the rack railway,the longitudinal instability should be avoided.The rail gap increases by 3.44%,and the pier abutment force decreases by 4.60%.(4)The research results could provide guidance for the design of CWR on bridges for rack railway.