On Free-Edge Effect and Onset of Delamination in FRPC Laminates Using Mixed Finite Element Model

Abstract

Free-edge stress analysis and the onset of delamination at the free-edges of FRPC laminates have been studied in the present paper. The stress analysis has been performed using a layer-wise 3-D mixed finite element model developed by the authors. Because the mixed FE formulation appropriately models the kinetics and the kinematics of laminated structures, the high stress gradients at the free-edge region of composite laminates have been appositely mapped. The onset of delamination failure has been computed using the tensor polynomial (quadratic) failure criterion. Results have been compared with the theoretical and experimental results available in the literature. It has been shown that the present results are in good agreement with the experimental observations.

Keywords

delamination free-edge effect mixed FEM failure theories tensor polynomial failure criterion.

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