An investigation into the effects of track structural conditions on railway track geometry deviations

Track geometry, consisting of several parameters, is the main factor influencing the ride quality and track performance. Railway authorities are spending considerably to maintain track geometry conditions within acceptable tolerance. Optimization of this expenditure requires a thorough investigation into the track structural factors influencing the conditions of track geometry. The current methods of track inspection are based on automated inspection of track geometry conditions, using track-recording cars. These methods have their limitations in identifying track structural defects, and in turn, lack the recognition of the causes of track geometry problems. There is a need to develop a track structural inspection and to investigate the relationship between track structural defects and track geometry problems. This research is an attempt to response to this need. The most dominant observable track structural distresses were studied, a track structural inspection method was proposed, and track structural conditions were quantified. A technique was developed to correlate track structural defects to track geometry problems. This technique was applied to tracks with various conditions, carrying out a comprehensive field investigation. The results obtained were analysed to identify the role of each track component on track geometry deviations, and in turn, develop correlations between track structural quality and track geometry conditions.