Fibre Area Correction Factors (FACF) for the extended rules-of-mixtures for natural fibre reinforced composites

The prediction of the properties of fibre-reinforced composite materials normally uses rules-of-mixture (RoM), but accuracy is constrained by the validity of data input to the model. A common error is the use of the fibre “apparent diameter” to determine the cross-sectional area of the polygonal fibre, and hence the fibre modulus and strength values are low. New equations are presented which can produce improved predictions of the in-plane moduli and strengths of natural fibre composites. Provisional data for the Fibre Area Correction Factors required by the new equations, based on recent publications in the scientific literature, are provided.