Conditioned Spectral Analysis in Multiaxial Fatigue

In multiaxial fatigue, a combination of random loads produces a complex state of stress at a point. These loads may be independent or partially related. Generally, the principal plane at the stress point varies with time which causes difficulty in assessing fatigue damage. This paper examines multiaxial stress using conditioned spectral analysis which, in certain circumstances, reduces the loads to a set of independent loads each of which is associated with a principal plane, allowing a separate assessment of fatigue damage with respect to each principal plane.