A Micromechanics Model for Compressive Failure of Unidirectional Fibre-Reinforced Plastics

Abstract

In this paper a method is presented for predicting the compressive strength of unidirectional fibre-reinforced plastics. Initial fibre misalignment and nonlinear shear response are included in the model which is based on a combination of other published methods. Predictions are shown to compare well with test data from an improved test method for carbon fibre-reinforced materials; one with an epoxy matrix and one with a PEEK matrix. Acceptable predictions are shown to depend on an appropriate assessment for fibre misalignment. The influence on compressive strength of moisture uptake by the composite was seen to be correctly predicted by the model.

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