桥梁跨度对跨座式单轨车桥耦合振动的影响分析

Analysis of the Influence of Bridge Span on the Coupling Vibration of a Straddle Monorail Vehicle Bridge

轨道梁结构对跨座式单轨车辆的稳定运行影响很大。为探究桥梁跨度对单轨车辆车桥耦合振动的影响规律,基于铁木辛柯理论和有限单元法建立连续的柔性轨道梁模型,运用多体动力学理论,通过UM建立单轨车辆车桥耦合动力学模型,在UM仿真界面设定不同的桥梁跨度和行车速度,仿真分析直线工况下桥梁跨度变化对车辆系统振动影响规律及运行平稳性的影响。结果表明:随着桥梁跨度增大,轨道梁跨中位移动力学响应值整体呈上升趋势,且当桥梁跨度超过16 m时,这种上升趋势更加明显;轨道梁跨中竖向加速度和轨道梁跨中横向加速度动力学响应值均随着桥梁跨度的增大而增大,然后又缓慢减小,桥梁跨度的变化对于轨道梁跨中横向加速度的影响较小;随着桥梁跨度增大,车体质心竖向位移动力响应明显增大,而车体质心横向位移略有减小;车体质心竖向加速度随着桥梁跨度的增大而增大,而横向加速度受桥梁跨度变化的影响很小。因为桥梁跨度增加会使单轨车辆运行的竖向平稳性指标和横向平稳性指标均有所增加,车辆运行平稳性变差。因此,将桥梁跨度控制在一定范围内对单轨车辆的稳定运行具有十分重要的意义。

The track beam structure has a significant impact on the stable operation of straddle type monorail vehicles.In order to explore the influence of bridge span on the vehicle-bridge coupling vibration of monorail vehicles,this paper establishes a continuous flexible track beam model based on the Timoshenko theory and the finite element method.Using the multi-body dynamics theory,the vehicle-bridge coupling dynamics model of monorail vehicles is established through the UM,and different bridge spans and driving speeds are set in the UM simulation interface.Simulate and analyze the impact of bridge span changes on the vibration response and operational stability of vehile systems under straigt line couditions.The results show that with the increase of bridge span,the overall mechanical response value of track beam midspan displacement shows an upward trend.When the bridge span exceeds 16 m,this upward trend is more obvious.The dynamic response values of the vertical acceleration and the lateral acceleration in the middle of the track beam span both increase with the increase of the bridge span,and then slowly decrease later.The change of the bridge span has a small impact on the lateral acceleration in the middle of the track beam span.As the span of the bridge increases,the dynamic response of the vertical displacement of the vehicle's center of mass increases significantly,while the lateral displacement of the vehicle's center of mass decreases slightly.The vertical acceleration of the vehicle's center of mass increases with the increase of the bridge span,while the change of the bridge span has little impact on the lateral acceleration.Since the increase in bridge span will increase both the vertical and lateral stability indicators of monorail vehicle operation,resulting in poor vehicle operation stability,controlling the bridge span within a certain range is of great significance for the stable operation of monorail vehicles.