Fatigue crack propagation model based on a local strain approach

The fatigue assessment of existing structures is becoming an important issue. However, an experimental fatigue evaluation of structural details is expensive. A numerical evaluation, while less expensive, is possible but often not practical since the existing numerical models have a narrow application range. This paper introduces a new fatigue model with a larger application range than the existing models. The new model is able to predict the fatigue behaviour of details made of structural steel that have been subjected to any load history, have any geometry, and contain any distribution of manufacture-introduced residual stress. Both the crack initiation and stable crack growth stages are considered. The model takes into account the influence of many fatigue-related aspects, such as crack closure, small crack behaviour, the specimen thickness effect, fatigue threshold and fatigue behaviour under cyclic compression.