DAMAGE ANALYSIS OF INTERLAMINAR FRACTURE SPECIMENS

Interlaminar fracture specimens are widely used for studying the inter laminar toughness of composite laminates. The goal of this paper is to analyse delamination specimens within the framework of a damage meso- modelling of composite laminates. In this type of modelling a laminate is described as a stacking sequence of homogeneous layers and interla minar interfaces. The interface is assumed to be damageable in order t o model the delamination phenomena. In the case of the propagation of a pre-existing crack, the main parameters for the interface model iden tification are the critical energy release rates. Delamination specime ns are here modelled as two beams connected by a damageable interface. By means of a Finite Element Scheme used in connection with a Riks-li ke algorithm; comparisons between numerical simulation and experiments have been performed for a wide class of specimens (D.C.B., E.N.F, E.L .S.). The results show the interest of the proposed modelling, which a llows a complete simulation of delamination using of relatively little experimental data.