An investigation of the influence of track dynamics on curve noise

Abstract

Experience has shown that curve noise issues can become more severe when curved track is upgraded from timber to concrete sleepers. This suggests that changing the dynamics of the track structure, for instance using a softer rail fastening system and/or sleeper, could provide ways to reduce curve squeal. The problem, however, is that the changes in dynamic characteristics between timber and concrete sleepers that explain the difference in curve noise behavior are not currently understood. Observations and anecdotes have hinted at the effect of different rail pads, fasteners, rail dampers and gauge relief on curve noise, but have failed to definitively identify either a successful mitigation strategy or a quantitative relationship with curve noise generation. This paper presents the results of field trials on curved track, conducted before and after an upgrade from timber sleepers to concrete sleepers, aimed at improving this understanding.