Evaluation of the probability density of inhomogeneous fiber orientations by computed tomography and its application to the calculation of the effective properties of a fiber-reinforced composite

This paper focuses on the experimental evaluation of one of the key microstructural parameters of a short-fiber reinforced composite - the orientation distribution of fibers. It is shown that computed tomography (CT) produces results suitable for reconstruction of the orientation distribution function. This function is used for calculation of the effective elastic properties of polymer-fiber reinforced concrete. Explicit formulas are derived for overall elastic moduli accounting for orientation distribution in the frameworks of the non-interaction approximation, the Mori-Tanaka-Benveniste scheme, and the Maxwell scheme. The approach illustrated can be applied to any kind of composite material.