Transverse moduli of continuous-fibre-reinforced polymers

This paper presents a closed-form micromechanical equation for predicting the transverse modulus, E2, of continuous-fibre-reinforced polymers. The equation was derived from a relatively simple mechanics-of-materials analysis of a repeating square cell. The assumptions made concerning the stress distributions and the typical matrix and fibre properties enabled the derivation of a closed-form expression. The present equation is in good agreement with a 3D finite-element hexagonal cell model and with Aboudiʹs method-of-cells equation, both complex approaches known to provide accurate predictions. Furthermore, combining the equation developed with other well-known equations, enables the calculation of the ν23 transverse Poisson ratio, thus completing the set of layer elastic constants needed for 3D stress analyses.