融合轨面短波不平顺的全波段高低不平顺谱表征及影响分析

Expression and Impact Analysis of Irregularity Spectrum of Longitudinal Level in Whole Wavelength Range by Integrating Rail Surface Short-wavelength Irregularity

轨道不平顺谱是表征轨道不平顺幅频特性的有效工具。目前,高速铁路轨道不平顺谱的研究主要聚焦在波长2 m及以上成分,甚少涉及轨面短波不平顺谱。基于大量无砟轨道高速铁路实测数据,研究轨面短波不平顺谱的表达函数及其与中长波轨道不平顺谱衔接的适应性。结果表明:两段幂函数能够很好地表征轨面短波不平顺谱。采用对数坐标系下的5阶多项式拟合全波段高低不平顺谱,实现中长波和短波成分在波长1~2 m范围内的平缓过渡。实测数据表明高速行车条件下,短波高低不平顺对轮轨垂向力及轴箱、构架和车体垂向加速度等指标均存在显著影响,全波段高低不平顺谱的建立对轮轨振动仿真分析、车辆和轨道结构设计以及轨道状态评估具有重要意义。

The track irregularity spectrum is an effective tool to characterize the amplitude-frequency characteristics of track irregularity.At present,the research on the track irregularity spectrum of high-speed railway mainly focuses on the wavelength range of 2 m and above,and rarely involves the short-wavelength irregularity spectrum of rail surface.Based on a large number of measured data of ballastless track of high-speed railway,this paper studied the expression function of the short-wavelength irregularity spectrum of the rail surface and its adaptability to the connection with medium and long-wavelength track irregularity spectrum.The results show that the two-piecewise power function can well characterize the short-wavelength irregularity spectrum of the rail surface.A 5th order polynomial in the logarithmic coordinate system was proposed to fit the whole wavelength range irregularity spectrum of longitudinal level,to realize smooth transition of the medium and long-wavelength and shortwave components between the wavelengths of 1~2 m.The measured data show that under the condition of high-speed train operation,the short-wavelength longitudinal level has a significant impact on the vertical force of the wheel and rail,as well as the vertical acceleration of axle box,frame and vehicle body.The establishment of the whole wavelength range irregularity spectrum has important significance for the simulation analysis of wheel-rail vibration,the design of vehicle&track structures and the evaluation of track state.