A quasi-brittle damage model for composite material is presented to analyze
progressive failure in composite structures. A rate independent constituti
ve law is expressed in terms of three damage parameters by using several po
lynomial failure criteria and a suitable micromechanical model. In order to
follow the damage evolution of laminated composite plates subject to monot
onic loads, a numerical procedure, based on a finite element approximation,
is developed. In particular, the material stiffness reduction is computed
by the proposed damage model and the number of global degrees of freedom is
reduced by using "clusters of laminae". Finally, both numerical and experi
mental data available in literature are compared with the results obtained
by the proposed numerical procedure. (C) 1999 Elsevier Science Ltd. All rig
hts reserved.