Author(s)

S. Holm, J. de Mare & T. Svensson

Abstract

Prediction of fatigue life based on level crossings and load history S. Holm," J. de Mare/ T. Svensson^ CWmera #,57, &JO^ Jf J ABSTRACT Models commonly used in fatigue life prediction are based on cycles counted in different ways. The most used method is based on Rain Flow counting which takes care of the stress history in a very specific way. This method has three main drawbacks. It is an ad-hoc way to produce cycles from a continuously varying stress curve. It introduces a memory in the cycle counting in a very rigid way and the algorithm is quite complicated. A model based on level crossings is on the other hand easy to apply but the level crossing spectrum does not contain enough information about the stress history. Here a model is proposed where the damage accumulation depends on the actual level crossing and the stress history condensed in a state variable, as well. The proposed model has the follow

Keywords