Analysis of vehicle/track interaction measurement data using the V/TI Monitor system

Abstract

The Vehicle / Track Interaction Monitor (V/TI Monitor) is one of the latest-generation systems for measuring quality of railway infrastructure elements which, with the help of accelerometers, measures and describes dynamic behavior of vehicles in interaction with the track. The VTI-TQI software was developed as a means to discover and interpret a considerable number of typical situations on railways involving simultaneous occurrence of various irregularities. The possibility for forecasting future development and growth of such irregularities was established through generation of appropriate deterioration trends.

Overview and analysis of methods for assessing ride comfort on tram tracks

“…This method, together with evaluation scales, is equivalent to the method described in EN ISO 2631-1 and EN ISO 2631-4, and includes the newly proposed weighting curve W b that is different from the curve W k that was presented in older versions of the standard [26]. The standard [4] suggests that time for averaging the vibration amplitude is 5 seconds. 5-second a rms values are used in the continuous comfort evaluation.…”

“…Table 6. Mean ride comfort N MV index scale according to [4] The N MV method has many similarities with the traditional vibration analysis according to ISO 2631-1. The controversial part is the use of the 95 th percentile where only the 4 th highest value is considered.…”

“…This paper describes experience gained during these studies and discusses further approaches for the evaluation of ride comfort. Vibration data gathered from in-service rail vehicles can be interpreted and applied in a variety of ways including: evaluation of ride quality (evaluation of vehicle performance and evaluation of infrastructure performance) [3] detection of faults on the track (welds, corrugation, rail breaks, track geometry) [4] detection of faults on vehicles [5] detection of faults on the overhead line [6] evaluation of passenger ride comfort in vehicles [7].…”

“…Motions of a vehicle are mostly measured by accelerometers and gyros fitted to the vehicle body at certain positions. Direct tests based on test subjects are not defined in EN 12299[4], but some guidelines are given in an informative annex.…”

Track ballast prism modelling by discrete element method

“…The level of deterioration of track structure can currently be determined quite accurately through load, using an appropriate device such as the V/TI (Vehicle/ Track Interaction) monitor, where accelerometers are used to measure and describe dynamic behaviour of rail vehicles in contact with track structure. This monitoring system enables determination of railway zones with irregularities and prediction of deterioration rate in such zones [7]. Load exerted by rail vehicle onto the track is imposed in a concentrated manner to rails, track accessories, sleepers that dissipate the load to a greater area and, finally, to the ballast prism and foundation soil (Figure 1).…”