Damage behaviour of laminated composites during fatigue loading

This study deals with the modelling of damage evolution in the carbon/epoxy laminated composites under static and fatigue loading. A cumulative damage model is developed on the basis of damage evolution due to static and fatigue during cyclic loading. A continuum damage mechanics (CDM)-based damage model coupling with the micromechanics has been utilized to predict the fatigue behaviour of laminate composites. A multicriterion approach has been introduced to predict the damage behaviour in the longitudinal, transverse, and shear direction at the ply scale. Extensive experimental results on T300/EPL1012 carbon/epoxy laminates are prepared to characterize under static and fatigue loading and to evaluate the proposed model in different conditions. The obtained results show that at the beginning of the cyclic loading, the damage grows suddenly and increases until final failure, which justifies the proposed method is able to predict the evolution of the damage due to static and fatigue loading separately during cyclic loading. The obtained results show that considering damage due to static loading leads to more accurate results, particularly in low-cycle fatigue.