CHARACTERIZATION OF TRANSVERSE CRACK AND CRACK GROWTH IN A RAILWAY RAIL

To ensure the rail transportations safety, evaluation offatigue behavior ofthe rail steelis necessary. high cycle fatigue behaviour of a rail steel was the subject of investigation in thisresearch using fracture mechanics. finite element method (fem) was used for analyzing thedistribution ofthe stresses on the rail, exerted by the external load. femanalysis showed that themaximum longitudinal stresses occurred on the railhead. to find out about the relation of crackgrowth with its critical size, and to estimate its lifetime, the behaviour oftransverse cracks to raildirection was studied using damage tolerance concept. it revealed that transverse crack growthinitially occurred slowly, but it accelerated once the crack size became larger. residual servicelife was calculated for defective segments of the rails. in addition, allowable crack size fordifferent non-destructive testing intervals was determined; the allowable crack size decreased asthe ndt intervals increased.