FE method to predict damage formation on curved track for various worn status of wheel/rail profiles
In wheel/rail contact, rolling phenomenon on the curved track can be much more complicated than that on the straight track, especially on a sharp curved track. Due to the influences of super-elevation (also called track cant), angle of attack (AOA) and rail cant, stress states on the high rail are significantly different from that on the low rail. Therefore, the appearances of damages on the low and high rails are different as well. These damages can result in the rail failures, subsequently leading to the vehicle derailments. In this paper, a realistic finite element model using Australian wheel/rail profiles (ANZR1 wheel and 60. kg rail) was developed to investigate the wheel/rail contact on the low and high rail of a curved track under high adhesion condition. Based on the datum of contact stress states, surface damage mechanisms of the rail in curved track was determined. The new and worn profiles were utilized in the simulation to examine different contact situations: new wheel/new rail, new wheel/worn rail, and worn wheel/worn rail contacts. The obtained results showed that the two-point contact might appear on the high rail of the curved track and the stress distributions at each contact location were varied depending on the contact location and AOA. Moreover, the response of material at the rail head was predicted to be ratchetting. Regarding the damage predictions, the rail corrugation tended to be formed on the low rail rather than the high rail; and the fatigue defects could be easier developed on the standard carbon rail compared with hardened rail.