Integrated safety factors in design for infinite and finite fatigue lives of steel elements at multiaxial static and periodic loadings

Abstract

The paper deals with strength calculations of steel elements under combined static and periodic loadings. Two design criteria, (i) and (ii), are presented which ensure that not only the multiaxial stress does not exceed the ultimate (or yield) strength of the material but also that the combination of multiaxial mean stress and multiaxial periodic stress does not lead to fatigue failure in design (i) for an infinite fatigue life and (ii) for a finite fatigue life. It is assumed that the stress components are physically independent of each other and that for each of them the corresponding o-N curve is given. The load modes and material anisotropy are taken into account.