A review of prediction methods for wheel-rail rolling contact was first prcsented. It is found that thc 3-D transient rolling contact model dcveloped using the explicit finite elemcnt method seems to be the most suitable approach for analyses of transient wheel-rail rolling-sliding-jumping contact at 400 km/h, or at higher speeds, and in the presence of short/medium-wave irregularities. Therefore, a transient rolling contact model was developed to simulate the dynamic curving of a wheelset on a typical curved track in the time domain. Harmonie or ideal rail corrugation was taken as the typical short/medium-wave irregularity to study its influences on transient rolling-sliding-jumping contact, with a wave-length ränge of 30-210 mm considered on the basis of field observations of high-speed wheels and rails in Operation. Be-sides corrugation geometry, corrugation oecurring on the high and/or the low rails was also taken into aecount properly, with the speed up to 500 km/h. Considering dynamic unloading caused by dynamics of low and medium frequency, the critical sizes of short/medium-wave irregularities were determined, at which the wheel-rail contact loss just oecurred. Fi-nally, proposals for management of wheel-rail short/medium-wave irregularities were discussed from the aspects of impor-tance, rationality and application limitations, and compared with the corrugation limit recommended for rail grinding Operations in Management Measures of High-speed Railway Rail Grinding.

A time-domain finite element model is developed to study the transient rolling contact of a driving wheelset over a curved track with Low Adhesion Zones (LAZs) shorter than 1.0 m. LAZs on one rail, i.e., unilateral LAZs occurring more likely, is treated for a speed up to 500 km/h. Structural vibrations of wheelset are analyzed to explain the transient contact forces, creepages and the resulting irregular wear. LAZs on high rails are found more detrimental than those on low rails. The results explain the occurrence of flats and rolling contact fatigue in bad weather, although significant wheel idling is absent.

Based on the measured spectra of rail roughness and track structures longitudinal roughness, the rail grinding limit is studied with the help of an established coupled dynamic metro vehicle–track model and a rolling contact fatigue model. The results indicate that metro rail grinding control should be regulated according to corrugation wavelength range and operating speed. Based on the rolling contact fatigue model, longer wavelength of rail corrugation has less influence on the wheel rolling contact fatigue. For the metro lines with a maximum operating speed of 80 km/h, the average levels of rail corrugation in the wavelength ranges of 30–65 mm, 65–125 mm, and 125–250 mm should be less than 5.4, 24.8, and 33.8 dB re 1 μm, respectively; for the ones with the operating speed of 80–120 km/h, the corresponding average corrugation levels in the three wavelength ranges should be less than 4.4, 9.8, and 29.8 dB re 1 μm, respectively.