Analytical expressions to estimate rapidly the notch stress intensity factors at V-notch tips using the Peak Stress Method

The Peak Stress Method (PSM) enables a rapid estimation of the notch stress intensity factors (NSIFs) for the fatigue strength assessment of sharp V-notches and notably welded joints. It takes advantage of the linear elastic peak stresses calculated at the V-notch tip using coarse finite element (FE) mesh patterns, thanks to properly calibrated coefficients depending on the V-notch opening angle, FE type, formulation, and FE mesh pattern typical of the employed FE code. The original calibration was performed only for few master values of opening angle; therefore, in the present study, the coefficients have been calibrated by using Ansys (R) FE code for the full range of notch opening angles to generalize the PSM. In particular, polynomial expressions have been fitted on the results of FE analyses and implemented in a tool that automates the application of the PSM. Two case studies have been analyzed highlighting the benefits of the new polynomial expressions.