Effective 3D constitutive relations of composites with evolving damage

In this study it is shown that a computational procedure, termed "discrete damage space homogenization method" (DDSHM), can predict the constitutive r esponse of layered composite materials containing growing cracks. The fully 3D effective constitutive law for a specific layered composite architectur e, as defined by the DDSHM, was integrated into the ABAQUS commercial finit e-element program using the user-defined material feature. Calculations wer e carried out for flat laminates with penny-shaped microcracks to illustrat e the computational efficiency of the method for general analysis of compos ite materials with growing cracks. Results show that, given basic informati on about the fracture toughness of the material, the DDSHM is able to predi ct important material parameters including the load at initiation of cracki ng, damage growth rate, and resulting effect on the macroscopic stiffness.