更快速度下周期性短波不平顺引起的轮轨高频振动特性及控制限值

Characteristics and control limit of wheel-rail high-frequency vibrations induced by periodic short-wave irregularities under higher operating speed

随着列车运行速度的不断加快,轮轨高频振动引起的车辆、轨道部件伤损问题更加突出,尤以周期性的短波不平顺最为常见。为了掌握轮轨高频振动自下而上的传递衰减规律以及制定合理的钢轨打磨策略,有必要针对车辆系统在高频激励条件下的耦合振动特性开展深入的理论研究。本文通过对大量实测数据的拟合,得到了更宽频段范围内的轨道高低不平顺谱拟合公式,并通过反演得到了0.002~100 m波长范围内的高低不平顺样本;在此基础上建立了高速动车组-轨道刚柔耦合动力学模型,其中对轮对、钢轨均考虑了弹性体振动模态,仿真分析了周期性短波不平顺引起的轮轨高频振动特性。结果表明,车辆各部件的振动频率分布范围为30~1390 Hz,且自下至上呈逐层衰减趋势。通过提取周期性短波不平顺幅值变化对轮轨相互作用的影响规律,进一步提出了适应400 km/h高速铁路的典型波长周期性短波不平顺的量化控制限值要求。

With the increasing speed of high-speed trains,the periodic short-wave irregularities caused by highfrequency vibration between wheel and rail inevitably cause potential severe damages to vehicle and track components.To gain an insight into the attenuation pattern of high-frequency vibration in the bottom-up transmission,it is necessary to investigate in-depth the vibration characteristics of the coupled vehicle system under high-frequency excitation.First,the spectrum of track irregularities with a wide frequency range is obtained via regression analysis of collected real measured data.Inversion analysis is followed conducted to obtain samples of irregularities within wavelength range of 0.002-100 m.Next,a rigid-flexible wheel-rail coupling dynamics model is built with the wheelset and the rail adopting elastic bodies.High-frequency vibration characteristics of the wheel and rail caused by periodic short-wave irregularities are then simulated and analyzed.The results show that the vibration of the vehicle components distributes in the frequency range of 30-1390 Hz,and the vibration attenuates from the bottom layer to the top layer.Finally,the quantitative limit value for the typical wavelength of periodic short-wave irregularities under the train speed of 400 km/h is further precisely calculated by extracting the influence of the amplitude variations of periodic short-wave irregularities on the wheel-rail interaction.