Notched Strength of Composite Materials

Abstract

A macroscopic model for predicting the strength of a composite laminate containing a circular notch is introduced. A property, which quantifies the reduction in strength of a given composite material or laminate due to a circular notch, is proposed. The superposition of notched strength data for several important composite material systems and laminate stacking sequences is achieved through development of a notched strength-radius superposition method and the definition of radius shift parameters, a_c and a_m . The superposition allows prediction of the in fluence of laminate stacking sequence upon notched strength. In addition, data for composite material systems or laminates of common stress concen tration factor is shown to superimpose by use of the developed shift parameters.

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