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Welded assemblies are commonly used in the shipbuilding industry. Thewelding process provides many possibilities and advantages for the design of complexstructures from simple geometric elements. (e.g., plates, tubes…). They are usually keyelements which contribute to the integrity of the structure and are subjected to complexand intense cyclic loading. Besides, welded assemblies contain geometricaldiscontinuities, which generate local stress and strain concentrations, and moreparticularly along the welding seam. Due to confined plasticity, nucleation of fatiguecracks can occur in these highly stressed regions and their growth could lead tofracture. Shipbuilding engineering and design department therefore need to haveefficient methods and resources to predict the fatigue behavior of welded assemblies.Fatigue analysis requires calculation of elastic-plastic stresses and strains at thecritical points of the structure (points of initiation for the fatigue crack). Elastic-plasticfinite element analyses could be performed but since the computational expense isprohibitive, other quick estimation methods were developed. The local elastic-plasticbehavior can be estimated using the purely elastic solution, (for instance Neuber’srule). However, the lack accuracy for multiaxial loadings in these methods led to a newapproach based on homogenization models which is used in this study. The stress andstrain histories thus determined will be compared to finite element computations and toexperimental results on double notched specimen whose material is a shipbuilding steel.Its behavior law is known from previous testing.