关键词:
Curve fitting
摘要:
Track irregularities significantly impair the safety and stability of vehicle operation. Identifying the sensitive wavelengths of medium- and long-wavelength track irregularities and establishing corresponding management limits for metro lines hold significant reference value for line maintenance. A rigid-flexible coupled dynamic model of a metro vehicle is established that takes into account the flexibility of the carbody. The model is then validated using measured carbody accelerations. Multi-cosine waves are used to model longitudinal-level, alignment, cross-level, and gauge irregularities. The influence of different wavelengths and amplitudes of these irregularities on vehicle dynamic performance is investigated and the range of sensitive wavelengths of track irregularities is determined. Finally, the simulation results are extrapolated to the management value of each dynamic performance index using curve fitting, and three levels of management limits for track irregularity amplitude are proposed. The results show that the sensitive wavelengths of metro track irregularities are mainly affected by vehicle suspension modes, car body flexibility modes, and bogie hunting motions. The four types of track irregularities that should be prioritized in the control of the wave band, together with their minimum amplitude limits, are as follows: longitudinal-level (1.5 ∼ 4 m and 6 ∼ 10 m, with minimum limits of 2.4 mm and 4.7 mm, respectively);alignment (10 ∼ 30 m, with a minimum limit of 1.6 mm);cross-level (1.5 ∼ 4 m and 6 ∼ 22 m, with minimum limits of 0.8 mm and 5.2 mm, respectively);gauge (10 ∼ 15 m, with a minimum limit of 5 mm). © 2025 Chinese Vibration Engineering Society. All rights reserved.