A damage meso-mechanical approach to fatigue failure prediction of cross-ply laminate composites

This paper focuses on the description and prediction of local fatigue damage development in fiber-reinforced cross-ply laminate composites. The transverse laminae and longitudinal laminae are homogenized and simulated by subcritical and critical effective laminae; and for each of them a meso-damage factor is introduced to represent the change of its in-situ elastic modulus. Based on the meso-damage theory, the redistributed local stresses in each lamina at the moment of crack saturation, or at the characteristic damage stage (CDS) are evaluated with measurable parameters of the laminate. This theory is therefore able to predict the CDS life and the stage II fatigue life of a cross-ply laminate. Experimental results of glass fiber/epoxy resin composite laminates are presented and found to be in agreement with the theoretical prediction.