Fatigue life prediction of the rail underhead region influenced by wear in heavy haul operations

Severe head wear combined with a transverse defect is considered as an increased risk for rail safety and integrity, and reverse detail fracture (i.e. transverse defects which initiate at the lower corner of the gauge face of heavily worn rail) could be produced. This defect type as observed in poorly lubricated, heavily worn curved rails on stiff track subjected to high axle loads is shown in Fig 1[1, 2]. Such failures which initiate at the underhead radius at aluminothermic welds are found in heavy axle load railway operation in Australia. Although, the weld normally has the lower material strength, the elevated residual stress levels and the complex geometry leading to stress concentration, the reverse detail fracture occasionally seen in aluminothermic welds but generally occur in the rail underhead.