Effect of Rail Irregularities on Ride Comfort of Train Moving Over Ballast-Less Tracks

Rail irregularities are the main factors influencing the ride comfort of trains moving over tracks. Despite various investigations made in this regard for the ballasted tracks, there is a lack of studies for the ballast-less tracks. This limitation is addressed in this study. To this end, a vehicle/slab-track interaction numerical model was developed, which was validated by comparison of the results obtained herein with those of the field tests carried out in this study. The effects of rail irregularities with various amplitudes and wavelengths on the ride comfort were studied by a comprehensive parametric analysis. Particularly, the effects of the wavelengths and amplitudes of rail irregularity on the ride comfort were investigated. Contrary to the current understanding, it was shown that rail irregularities with short wavelength have considerable effects on the ride comfort for the slab-tracks. In addition, the ride comfort decreases significantly when the wavelengths of rail irregularity become less than 0.75[Formula: see text]m in the metro lines. The critical speed of the train (at which the lowest ride comfort is obtained) was derived as a function of rail irregularity. The results obtained indicate that the amplitude of rail irregularity has negligible influence on the critical speed of the train.