Abstract: On the basis of the stress field intensity approach, a theory of local stress-strain field intensity for fatigue damage at notch is presented , which considers the effects of the local stress-strain’s gradient on fatigue damage. A local stress-strain approach to fatigue life prediction at notch under random loading is proposed. This method is used to predict fatigue crack initiation life, and it is shown that it is a good correction with the experimental results.

Key words: Elastic-plastic finite element, Fatigue life prediction, Local stress-strain field intensity, Random loading