Simulations of dynamic vehicle performance were used by the Wheel Defect Prevention Research Consortium (WDPRC) to explore which track and vehicle variables affect wheel fatigue life. A NUCARS model was used to efficiently examine the effects of a multitude of parameters including wheel/rail profiles, wheel/rail lubrication, truck type, curvature, speed, and track geometry. Results from over 1,000 simulations of a loaded 1,272 kN (286,000-pound) hopper car are summarized. Rolling contact fatigue (RCF) is one way that wheels can develop treads defects. Thermal mechanical shelling (TMS) is a subset of wheel shelling in which the heat from tread braking reduces a wheel's fatigue resistance. RCF and TMS together are estimated to account for approximately half of the total wheel tread damage problem [1]. Other types of tread damage can result from wheel slides. The work described in this paper concerns pure RCF, without regard to temperature effects or wheel slide events.
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