Rail temperature forecasts over different time-ranges for track applications

Rail temperature is one of the key parameter of track integrity and stability because of rail breaks which may arise at low temperatures and because of track deformations which may arise at high temperatures. This is why rail temperature is at stake for different time ranges over track life, from design stages where track structure must be made able to support expected temperature variations, to daily control where combination of thermal stresses and other factors shall not impair overall track stability. Engineering track regulations worldwide strongly stress rail temperature to be a major issue in connection with continuous welded rail. Up to recently, a security margin has to be kept in engineering regulations so as to be relevant with any hazard caused by air temperature values exhibiting random values. However, it is shown in this paper that recent technological advances allow for track engineers to get easier rail temperature forecast, with a better assessment of risk level.