Influence Of Track Irregularity Characteristics In The Frequency Domain To The Vehicle Dynamic Performance

On the railway line, the quality of the railway will directly affects the vibration situation of the vehicle-railway system. Track irregularity will cause lateral and vertical vibration of the vehicle, increasing the rail-wheel forces and even derailment, which seriously impact the safety, stationarity and comfort. The situation of the track reflects the integrated performance and carrying capacity, which is the core issue of railway line management. Therefore, it’s essential to take a research on the track irregularity features to ensure the security operations. This paper mainly analysis the impact of track irregularity frequency domain characteristics on rolling stock running stability, which will provide reference for the management and maintenance of the railway line.Firstly,we will shortly introduce the reasons, effects, classification and characteristics of the track irregularity, knowing that track irregularity has randomness, which we can analysis from time domain and frequency domain. Also, we takes an overview of track irregularity power spectrum and of the conversion between time domain irregularity and the power spectrum.Secondly, based on the measured irregularity data of South Africa narrow-gauge line-NAM531A, we divides the track into several continuous sections as the samples of track irregularity and gets the time-domain spectroscopy. Then converse each sample from time-domain spectroscopy to power spectrum.By analyzing the time-domain spectroscopy and power spectrum, it can evaluate the track irregularity situation in Line-NAM531 A.At the same time, aiming at the number of the frequency and wavelength range in frequency domain based on the German high excitation train irregularity spectrum as track incentive, we sets 3 different conditions and analysis its time-domain waveform characteristics.Finally, construct the locomotive dynamic model in SIMPACK, choose the samples and 3 conditions as track incentive and then calculate the running stability, by which compare the locomotive stationary state of each section on the Line-NAM531 and analysis the impact of track irregularity frequency domain characteristics.Above all, vertical stationary of the locomotive is better than lateral stability in Line-NAM531A and the vertical track quality is better. The magnitude of the mean square value in time-domain spectroscopy of track irregularity, power spectrum value, wavelength range and frequency numbers have larger effect on running stationary of the locomotive. It should take the eigenvalue above into consideration in line maintenance, management and dynamic performance simulation.