Improvement of fatigue life prediction accuracy for various realistic loading spectra by use of correction factors

Abstract Some examples of using the correction factor method for improving the fatigue life prediction accuracy using the nominal-stress and local-strain approaches are considered. The ratio Nexp/Ncalc for a relevant loading spectrum was used to predict the fatigue life of a component loaded under a second spectrum with a similar loading frequency distribution. It is shown that the application area of the relative method is similar both for the nominal-stress and local-strain approaches. In the second case, correction is especially needed so that more reliable estimates are obtained. For both approaches, predictions are much improved when the two compared loading cases differ only in the reference stress level, or when the reference stress level and some other important loading spectrum parameters are identical but the loading frequency distribution differs somewhat.