Modelling the mean stress effect on fatigue life of fibre reinforced plastics

The mean stress influence on fatigue life of carbon and glass fibre reinforced plastics is investigated in detail. A new phenomenological approach is presented to model the mean stress effect in various material systems and fibre dominated stacking sequences. The model is calibrated to fatigue data via a developed fitting-routine that is based on least squares method. The calibration input data is one Woehler curve at R = 0.1 and the ultimate static strengths in tension and compression loading. The characterization effort is reduced by this significantly. Finally the method is verified successfully by fatigue data of several material systems.