Analysis of Correlation between Stresses and Fatigue Lives of Welded Steel Specimens Based on Real Three-Dimensional Weld Geometry

Welded joints are areas of increased stresses in construction. The reason for this phenomenon is associated with the nonhomogeneous mechanical, structural and geometrical properties of the weld. In the article the correlations between locally raised stresses due to real geometry and fatigue lives of non-load carrying cruciform joints made from S355J2+N steel are analysed. Stresses were computed using Finite Element Method (FEM) based on real three-dimensional weld geometry obtained by 3D scanning. The specimens were experimentally tested under cyclic push-pull loading with a zero mean value of applied force. The correlation was analysed using Pearson’s correlation coefficient and statistical hypotheses. It was shown that statistically significant correlation exists between maximum values of normal stresses and fatigue lives.