Theoretical Model for Dynamic Wheel/Rail and Track Interaction

A wheel/rail and track dynamic interaction model is presented. The wheelset model includes two unsprung masses, the side frame mass and pitch inertia, and the primary suspensions, all pertaining to one rail. The track is a 40-tie long discretely supported system of elastic beams representing the rails and ties. Springs and dashpots represent the stiffness and damping effects of the rail pads and the track bed. A non-linear Hertzian contact spring couples the wheel and the rail track system. Numerical examples consist of wheel/rail impacts due to a wheel flat, a corrugated rail, and a wheel shell.