Discrete element modelling of rolling contact fatigue and crack closure with different bond laws

The prediction of rolling contact fatigue requires modelling methods that efficiently simulate the propagation, branching and coalescence of fatigue cracks. The developed Discrete Element Method (DEM) model is a novel approach to provide this capability. The model is based on discrete elements (bonds) that are subject to a fatigue law. With it, the failure of elements due to cyclic loads can be simulated. The propagating cracks are not confined to predefined paths, but develop according to the local loading conditions. These conditions depend on an appropriate set-up of the element interaction, i.e. the bond law, which is calibrated, taking into account crack closure effects. The method delivers a relevant improvement for DEM- and peridynamic models, where compressive loads dominate. The current development of the model is summarised in this paper.