A damage model for simulation of mixed-mode delamination growth

An interface element capable of modelling delamination progression under mi xed-mode loading is presented. The kinematics of the element are based on t he concept of regularised displacement discontinuity. This concept allows t he interfacial constitutive equations to be formulated in terms of the trac tion vector of the interface and the corresponding displacement discontinui ty. The decohesion within the interface, corresponding to delamination prog ression, is accomplished by assigning a non-associative perfectly plastic m aterial model including isotropic damage to the interface element. All para meters of the model can be determined from experimental material data. Dama ge initiation is calibrated against the interlaminar fracture stresses wher eas the evolution of damage is calibrated against the mixed-mode fracture t oughness. The interface element has been implemented in a finite element co de and results for simulations of standard fracture toughness tests are sho wn. The results display the applicability of the proposed model and the cal ibration procedure. (C) 2001 Elsevier Science Ltd. All rights reserved.