Partial Slip Rolling Wheel-Rail Contact With a Slant Rail Crack

This paper investigates the tip characteristics of an oblique crack in the wheel-rail contact problem. The wheel-rail normal contact pressure and interfacial shear stress distributions, and the stress intensity factors (SIF), are studied for oblique cracks of different inclinations, and the variations in both contact stress distributions near the crack edge are simulated under normal and traction loads, respectively. Contact elements are employed to model the interactions between the wheel-rail contact surfaces and the crack surfaces, respectively. The effects of crack orientation, crack length, and contact distance on the contact stress distributions and stress intensity factors, KI and KII, are investigated. The results indicate that a wheel-rail traction force reduces KII significantly as the contact point travels over the crack edge. Furthermore, fluctuations in KI and KII are very significant with regard to early squat propagation of cracks. The results also demonstrate that applying Carter’s contact model or the full slip contact model to the same wheel-rail contact crack problem yields significantly different stress intensity factor values.