ON AN INTER-SCALE MODEL FORMATRIX FAILURES IN COMPOSITE LAMINATES

摘要

This article presents an inter-scale failure theory for matrix tensile failures that occur in laminate plies.The theory is based on two key postulations: one is the existence of a probabilistic tensile strengthparameter between adjacent fibers; the other is related to the fiber-packing connectivity that affects matrixcracking. Both postulations need experimental correlation; for this, a test method is described. To applythe theory, detailed stress fields at the fiber-matrix scale must be recovered after the analysis of laminatesunder specific loading; then, matrix tensile cracks that occur in laminates can be simulated without furtherexperimental correlation. For illustration purpose, a model composite system is used in two matrixcrackingcases: one is the 90o-compact tension specimen with or without a side-crack; the other is relatedto transverse cracking in cross-plied laminates under longitudinal tension; both problems are nowclassical; but a satisfactory model for the critical loads causing matrix cracking has not here-to-fore beenavailable.