Infrastructure managers are devoting a large amount of effort to ensure that the integrity of the rail track network is preserved by conducting regular inspections involving up to date NDE techniques. Nevertheless, the development of cracks in rails is unavoidable. The rail damage prediction tools (such as VAMPIRE) currently employed by the industry are based on empirical relations based on the cumulative damage sustained by the axle weight and volume of traffic passing over a rail (J. Evans, 2003). These models do not take into account the development or presence of flaws. It can be stated that decisions on replacement of a rail are not made on the basis of a fracture mechanics based flaw severity assessment (a damage tolerance approach).
This work has undertaken the study of fatigue cracks in rails using FEA modeling and analytical solutions to provide a tool to rail NDE inspectors for the quick assessment of the severity of surface breaking and embedded cracks in rails. The work does not investigate crack initiation and propagation phenomena on the heads of rails, but concentrates mainly on cracks initiating and propagating from bending loads in the foot of the rail as a result of passing trains.