Finite Element Based Degradation Model for Composites with Transverse Matrix Cracks

Abstract

A degradation model for predicting the effective homogenized threedimensional elastic constants of an interior ply with transverse matrix cracks was developed by analyzing a three-ply representative volume element using the finite element method. The degradation model was first evaluated by comparing the homogenized extensional modulus for a cracked [0/(⁹⁰)3]s laminate with experimental results and finite element discrete models in which each crack was modeled discretely. Further, using the degradation model, the prediction of load redistribution for a cantilevered laminated plate with matrix cracks subjected to transverse end load was compared with a discrete crack model. Also, the prediction of load redistribution in a cracked plain weave composite subjected to uniaxial stress was compared with a discrete crack model. The degradation model showed good agreement in predicting the homogenized elastic constants and load redistributions.

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