2024

Yanchukovich Alexei; Ahola Antti; Björk Timo; Sonsino Cetin Morris

In fatigue assessments, local strains and stresses can be easily evaluated using accurate finite element analysis in a case of an individual fatigue-critical notch or structural detail. In practical design and analysis of global models, the consideration of local notch effects using suitable estimation rules in the combination with linear elastic analysis is reasonable. Various notch rules exist but the current knowledge lacks understanding how applicable different notch rules are for estimating notch strains from elastic stresses. This work studies the Neuber’s rules for sharp and mild notches, Glinka’s equivalent strain energy density method, the correction of Neuber’s rule proposed by Sonsino for mild notches, as well as the Seeger-Beste method. The application of different estimation rules for notch strains, applied to the elastic-perfectly plastic steel material and to Ramberg-Osgood material model for the aluminum material, including work hardening effect, was studied in this work by comparing the estimations with the corresponding experimental data and finite element analysis results. The Neuber’s rule for mild notches and Sonsino’s averaging method gave best correlations with the experimental data and numerical (finite element analysis) results and can be thus recommended for such analyses in compatible cases studied in this work.