Failure analysis of unidirectional fiber reinforced plastics based on computational micromechanics and PUCK failure theory

Abstract

Achievement of accurate and reliable failure criterion is fundamentally important for designing composite structures. This study comprehensively evaluated the failure of unidirectional fiber-reinforced plastics (FRP) from the perspectives of failure theory and computational micromechanics. Further, PUCK failure criterion was analyzed in detail to identify the specific effects of the interfacial reinforcement coefficient on the failure mechanism. The representative volume element model of FRP with randomly distributed fibers was established. The comparative analysis of the results between current failure theory and experiment, indicates that the load bearing capacity of FRP under bi-axial compressive stress and shear stress is understated by the PUCK failure criterion. Microscopic finite element analysis was adopted to investigate the failure envelope of FRP, considering interface reinforcement coefficient. The results reveal that the strength of FRP under the combination of moderate transverse compressive stress and in-plane shear stress is significantly affected by the interface reinforcement coefficient. The accuracy of PUCK failure criterion heavily depends on the value of the interface reinforcement coefficient and if the criterion does not consider the coefficient, it can cause notable error on strength prediction. Consequently, determination of interface reinforcement coefficient would be helpful to achieve more accurate failure criterion for FRP.