Optimizing the Voce–Chaboche Model Parameters for Fatigue Life Estimation of Welded Joints in High-Strength Marine Structures

This work studies the Voce–Chaboche (V–C) material model parameter optimization for high-strength steel welded joints subjected to cyclic loading. The parameters of each zone in a S690 butt-welded joint were determined using an algorithm based on Newton trust region (NTR) method and accumulated true strain parameter. fitted stress–strain histories from uniaxial strain-controlled tests. To validate model, fully-reversed variable amplitude fatigue experiments performed under load control. experimental results then compared numerical finite element analysis. When elastic modulus is optimized as V–C parameter, indicate that slightly underestimates range, leading conservative life estimates. However, can be improved by obtained experimentally. In this case, resulting overestimates non-conservative, but more accurate, estimation. It concluded NTR-based approach successfully different zones joint, closely estimated range history.