Author(s)

J. Droździel & B. Sowiński

Abstract

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. Keywords: track, vehicle, dynamics, simulation, deterioration. 1 Introduction Modern railway track is an important factor in providing a good transportation system. Large sums of money are dedicated to the railway track maintenance and renewal. Formerly, most attention has been given to the track superstructure (the rails, the fasteners and the sleepers), and less attention has been given to the substructure (the ballast, the subballast and the subgrade). Although these substructure components have a major influence on the track quality, less attention has been given to them because the properties of the substructure are more sophisticated then the properties of the superstructure. This paper shall be restricted to examining the influence of the elastic and damping properties of the ballast on the track settlement and deterioration of its

Keywords

track, vehicle, dynamics, simulation, deterioration.