A Constitutive Model for Elastic Damage in Fiber-Reinforced PMC Laminae

A practical methodology is presented for modeling the damaging behavior of fiber-reinforced, polymer-matrix composite laminae. It accounts for the basic mechanisms of degradation of properties under mechanical loading and incorporates this knowledge into a simple constitutive model in the framework of Continuum Damage Mechanics. A new expression for the damage surface is proposed, which reduces to the expression of the Tsai-Wu failure criterion in stress space. Model identification allows us to characterize the material through a small number of material parameters, all of which are related to material properties available in the literature. Available experimental results are used to illustrate the proposed methodology.