既有铁路曲线桥线路偏心对列车安全运行的影响分析

Influence Analysis of Eccentricity of Existing Railway Curve Bridge Line on Safe Operation of Train

以既有线铁路桥梁为研究对象,基于车-桥耦合振动理论,建立可以考虑线路偏心作用影响的车-桥耦合分析模型,研究线路偏心作用对脱轨系数、轮重减载率、轮轨横向力、桥梁振动响应等指标的影响,以及各指标随行车速度的变化规律。研究结果表明:线路偏心作用对车辆系统的轮轨横向力影响最大,轮重减载率次之,且对机车的影响大于客车影响;线路偏心作用对桥梁系统的横向位移、墩顶横向位移比其他指标大。当车辆以不同速度通过偏心曲线桥梁时,轮重减载率、脱轨系数、轮轨横向力均随速度的增大而增大,且轮轨横向力增长率最大,轮重减载率次之,而桥梁跨中横向位移、墩顶横向位移均随速度先减小后增大。T梁内侧梁竖向位移随速度增大而减小,外侧梁竖向位移随速度增大而增大。偏心线路应以轮轨横向力作为衡量指标,防止轮轨横向力过大导致扣件破坏、轨排横移。

Taking a existing railway bridge as the research object,based on the theory of vehicle-bridge coupling vibration,a vehicle bridge coupling analysis model that can consider the influence of line eccentricity was established.The influence of line eccentricity on indicators such as derailment coefficient,wheel load reduction rate,wheel rail lateral force,and bridge vibration response was studied,as well as the variation law of each indicator with driving speed.The results show that the eccentricity of the line has a significant impact on both the vehicle and bridge systems,with the largest impact on the wheel/rail lateral force of the vehicle system,followed by the wheel load reduction,and the impact on locomotives was greater than that on passenger vehicles,and the lateral displacement and pier top lateral displacement of the bridge system were greater than other indicators.When vehicles pass through an eccentric curve bridge at different speeds,the wheel load reduction,derailment coefficient,and wheel/rail lateral force all increase with the increase of speed,and the wheel rail lateral force growth rate was the highest,followed by the wheel load reduction.The bridge mid-span lateral displacement and pier top lateral displacement first decrease and then increase with the speed.The inner girder of the T-girder decreases with the increase of speed,and the outer girder increases with the increase of speed.The wheel/rail lateral force should be used as an indicator to prevent excessive of wheel/rail lateral force from causing damage to the fasteners and lateral displacement of the track panel.