Simulation of railway track deterioration influenced by ballast stiffness and dry friction

It is known, that track deterioration (loss of its geometry) strongly depends on track support conditions, particularly on the ballast. In this paper a novel approach is presented to predict the evolution of track vertical irregularities due to vehicle-track dynamic interaction taking into account ballast stiffness with dry friction. An applied vehicle-track model is composed of a railway car and a track. The track is assumed to be a discrete system having a series of inertial elements, which are elastically coupled. The vertical ballast stiffness may fluctuate along the track and its damping is described by dry friction with the friction force depending on wheelset loading. In the track model, initial irregularities may be introduced to initiate the process of track deterioration and vertical track irregularities expansion. Simulation results are evaluated for a series of rail car passing and referred to other results.