A Study on the Damage of Reinforced Material

A micro-mechanical approach is used to discuss the damage of two solid phases firmly bonded together at the interfaces. A theorem of theoretical as well as of practical importance is presented. It relates the damage properties of composite material and its constituents. Conditions on the constants of constituent and composite material have been imposed to predict the superiority of composite material. The mixture is assumed to be homogeneous on a microscopic scale, but not necessarily isotropic. How ever, the two phases themselves are assumed to isotropic and homogeneous. But their elas tic moduli differ and so that the stress and the strain fields throughout the mixture are microscopically nonhomogeneous.