2D fatigue crack propagation in rails taking into account actual plastic stresses

Due to increase axle loads, repeated passages of the wheels, rolling contact fatigue cracks initiate in the surface or subsurface of the rails. These defects can propagate and lead to the rail failure. A two-scale frictional contact fatigue crack model developed within the X-FEM framework is used to address the cracked rail problem, calculate the stress intensity factors, perform crack propagation and fatigue life prediction. Actual plastic stresses, quantified through a dedicated software developed by SNCF within the consortium IDR2, are taken into account in the propagation simulation via projection of the asymptotic mechanical fields. The effects of those actual plastic stresses are investigated on the crack growth path and rate. Interactions between multiple cracks of a network are also analyzed.