Predicting deterioration in track condition

The author suggests that a more precise understanding of the factors influencing ballasted trackbed deterioration is necessary in order to better inform the choices made in trackbed design. The problem is one of differential settlement and in order to examine this a 2-stage procedure is adopted: a) an analysis of the settlement of a single sleeper in response to repeated vertical load and b) modelling of the interaction of track unevenness and induced dynamic load leading to uneven load distribution. The settlement of a single sleeper is measured using Nottingham University's Railway Test Facility. This facility is a full scale 3-sleeper rig with a realistic trackbed construction which allows loads to be applied and measurements taken of sleeper settlement. In order to examine differential settlement a model is developed based on the vertical oscillation of a single carriage end on its suspension system. Variables are examined including axle weight, train speed, subgrade stiffness and sleeper spacing and provisional results presented. The author concludes that such an accelerated predictive approach would be useful in trialling new products and would provide a more scientific basis to trackbed design.

Language

  • English

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Filing Info

  • Accession Number: 01146951
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Dec 24 2009 8:32AM