ABSTRACT
ABSTRACT: The assessment of track geometry defects is an important requirement for safe rail operation. According to current standards it is based on the amplitudes of the track defects. Thresholds are defined whose exceedance implies maintenance or speed reductions. The threshold values are based on experience and have proved their use. However, derailments have been reported for which all track geometry parameters were within the standards. Investigations revealed that the dynamic response of the vehicle depends not only on the amplitude but also on the combination and repetition of single track defects. This work proposes a classification of track defects taking into account these track characteristics. It is analysed under which conditions the different defect classes appear. Finally, the impact of the defect classes on the vehicle response will be studied. This may allow the identification of critical situations and the adaption of maintenance to vehicle requirements.
