Modelling Rail Track Performance: An Integrated Approach

This paper reports on the work undertaken at the Queensland University of Technology to develop an integrated computer based tool for the prediction of track behaviour under changing traffic conditions. The track degradation model described here takes into account the degradation effects due to the interactions between track components. The model uses mechanistic relationships and embraces all the major factors which may influence service life of track components. The model was applied to a typical Australian railway track and the results are summarised here. The results showed that increasing axle load and train speed accelerates track degradation in general and rail wear in particular. Sub-grade stiffness and ballast depth are found to be the most important parameters for track roughness. Timber sleeper failure is sensitive to both traffic parameters and environmental factors, such as the decay index and track drainage condition. Increases in axle loads may not lead to higher sleeper damage failure rate at fixed traffic loads. Decay index, track drainage condition and average age of sleepers, all have a noticeable effect on sleeper failure