2. Local elastoplastic approach and Neuber's rule

The local elastoplastic approach, detailed in reference , is based on the observation that most fatigue cracks start from a geometric accident (notch, groove, thread, hole) and that the local concentration of stresses leads the material to exceed its elastic limit, either at each loading cycle (accommodation), or during the first few loading cycles before returning to elastic behavior (adaptation).

In this case, it is no longer sufficient to simply use elastic strength-of-materials or finite-element calculations. Cyclic plastic deformation must be taken into account to determine the local stresses...