ABSTRACT

ABSTRACT: Starting point for the investigations are two accidents with 2-axle freight waggons with which the accident reason is unknown. The analysis of the track geometry of both accidents shows a periodic rail irregularity in vertical direction, but these are within the limits according to the german guideline. A linear analysis of the track excitation and the vehicle shows a matching between the excitation frequency and the vehicle eigenmodes. With the multi-body simulation software SIMPACK the derailment reasons are analysed. On the basis of variations in number, amplitude and vehicle speed of a derived synthetic track irregularity it can be pointed out, that under certain conditions a derailment can occur although the track irregularities are within the limits.