Dynamic ananysis of vehicle-track coupling system due to a wheel flat

This paper presents the responses of the vehicle and track components in terms of vertical forces and displacements. The considered vehicle model is a 10-DOF multi-rigid-body system supported on a track systems that consider three layers of structure. The car body is linked with the bogie through the secondary suspension system contained spring and damper elements. In the model of track, the rail is considered as an infinitely long beam discretely supported by a series of springs, dampers and masses representing the elasticity and damping effects of the rail pads, ballasts, and subgrades respectively. The non-linear Hertzian contact theory is employed to solve the vertical contact force between the wheel and the continuous rail. The result further showed that the variation in axle load do not influence the oscillation frequency of the vertical force.