Abstract
This paper pursues the interest in characterizing stress concentrations in composites for the purpose of providing more reliable input into statistical theories about composite strength. A previous paper estimated stress concentration parameters in a fibre-matrix composite by numerical maximum likelihood, using the chain of bundles model of Harlow and Phoenix. An assumption of the model is that bundles are independent. Here, a model is proposed which allows for a dependence across bundles, usually due to the extent to which a fibre becomes unstressed in the region of a break. The model is demonstrated using experimental data on a carbon-epoxy hybrid composite, and arrays of tungsten-cored silicon carbide fibres embedded in resin. It is shown, via the method of maximum likelihood, how inferences may be made about stress concentrations and also parameters describing single fibre strength.
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Wolstenholme, L.C. A dependent bundles model for estimating stress concentrations in fibre-matrix composites. J Mater Sci 26, 4599–4614 (1991). https://doi.org/10.1007/BF00612394
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DOI: https://doi.org/10.1007/BF00612394