Fatigue failure assessment of S355J2G1W structural steel under biaxial in- and out of phase loading regarding geometrical constraints of samples

The paper presents the fatigue tests results of the different samples configurations subjected to the biaxial type of loading. All test were performed for structural steel. The experimental campaign was conducted with non-proportional bending and torsion without and with phase shift equal to phi = 0 degrees and 90 degrees for various stress ratios. One-sided restrained samples were tested under constant load and constant stress ratio R = -1. The development of fatigue cracks was also observed and recorded during the tests. Stress distributions were numerically calculated using the Matlab program. Lifetimes calculated according to modified Huber-Mises, modified Tresca and Nishihara-Kawamoto criteria are compared with experimental ones.