Fatigue life and crack path predictions in generic 2D structural components

This paper proposes a reliable and cost-effective two-phase methodology to predict crack propagation life in generic two-dimensional (2D) structural components. First, the usually curved fatigue crack path and its stress-intensity factors are calculated at small crack increments in a specialized finite-element software, using automatic remeshing algorithms, special crack tip elements and appropriate crack increment criteria. Then, the computed stress-intensity factors are transferred to a powerful general-purpose fatigue-design program, which has been designed to predict both initiation and propagation fatigue lives by means of classical design methods. Particularly, its crack propagation module accepts any KI expression and any crack growth rate model, considering sequence effects such as overload-induced crack re-tardation to deal with 1D and 2D crack propagation under variable amplitude loading. Non-trivial application ex-amples compare the numerical simulation results with those measured in physical experiments