2. Wheel-rail interface

Dynamic behaviour of the rail vehicle strongly depends on the physical properties of the interface between vehicle and the track, namely the wheel-rail interface that has the functions to support and guide the train on the track, to transmit traction and braking forces and to keep the vehicle inside gauge envelope. All the forces exchanged between the vehicle and the track are concentrated on the contact patch, in an area of 1 to 2 cm ² . The high accelerations and loads and the cyclic stresses on the wheel-rail contact can result in structural or geometric damages of the wheels or rails and in vibrations on vehicle parts, impacting negatively the running safety, track fatigue loads and ride quality & comfort. Compared with road transport the wheel-rail (w-r) contact area is hundreds times smaller than tire-road contact area ; the speed and...