Fatigue crack growth in a welded rail under the influence of residual stresses

The effect of welding residual stresses on fatigue crack growth in rail welds is studied. Finite element analysis is used to calculate residual stresses in a flash-butt welded rail. The calculated residual stresses are found to be in good agreement with experimentally determined residual stresses in a welded rail. The redistribution of residual stresses in the welded rail is simulated for a straight track, during heavy-haul operation conditions, using a train-track model. Fatigue crack growth of defects in the weld region is studied using fracture mechanics. In the investigation, a number of parameters such as the axle load, crack location, crack size and rail temperature are varied.