The experimental characterization of the mechanical properties has always been a key issue in the research on composite materials. The validity of micromechanics analyses, determining the composite macromechanical properties with constituent material properties, can be confirmed by the result of experimental characterization. For a unidirectional lamina, there are four independent elastic constants; the elastic moduli in the longitudinal and transverse directions; the shear modulus; the major Poisson's ratio.
For soft matrix composites, such as rubber-matrix composites, it is difficult to determine the mechanical properties by existing method due to their low shear modulus in contrast to hard matrix composites. In this study, the experimental and finite element analysis of a fiber-reinforced rubber-matrix composite material are carried out for both regular and irregular specimens. According to their aspect ratio, specimens are classified to regular specimen which has high aspect ratio and irregular specimen which has low aspect ratio. The finite element analysis of the composite material is carried out for the equivalent plane stress model including the effect of kinematic nonlinearity. Material properties determined by both the experiment and finite element analysis are well coincide with the micromechanics analysis, Halpin-Tsai equation.
For the soft matrix composites, such as fiber-reinforced rubber-matrix composites, the presented experimental and finite element analysis are applicable to determine the mechanical properties.
