Fatigue Crack Paths 2003

torsion) show that the hypothesis of no interaction leads to unsatisfactory predicted

fatigue lives. In other words, one has to admit that the different kinds of oriented

damage interact. If this interaction is not taken into account in a model, the predictions

are likely not to be conservative.

A critical plane damage model based on a microplasticity analysis has been used to

confirm this trend. The predictions are proved to be very good when a purely linear

damage accumulation process is assumed to act between two non similar loadings. The

hypothesis of no interaction leading systematically to non conservative predictions.

R E F E R E N C E S

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