Wheel surface damage: relating the position and angle of forces to the observed damage patterns

A new method of presenting simulated wheel/rail forces and relating these to the observed wheel
damage has been developed. This indicates a good correlation between the predicted forces and the
regions of the wheel where damage is observed in practice. There is also a good correlation between the angle of the predicted forces and the observed cracks. The angle evidence suggests that the dominantrolling contact fatigue cracks on the field side of the wheel tread are initiated by the occasional high forces when the opposite wheel is running in flange contact on sharp curves. Cracks may then be propagated by more frequent lower forces on moderate curves.