Mixed mode delamination in plates: a refined approach

Abstract

Abstract Energy release rate and its mode partition in layered plates are analysed by using an improved laminated plate model. The adhesion between layers is modelled by means of a linear interface acting in the opening and sliding failure mode directions. Stress singularities at the crack tip are recovered when the stiffness of the interface approaches infinity. Kirchhoff or Reissner–Mindlin plate models are employed to describe the layers. Analytical solutions of the relevant governing equations are obtained through a variational formulation of an augmented total potential energy, in which the stiffness of the interface introduces kinematics constraints in the form of a penalty functional. Closed form solutions for energy release rates are given evidencing the effectiveness and the simplicity of the proposed model. Comparisons with fracture mechanics results––when available––are shown discussing the validity of the proposed mechanical model to predict mode partition. Interesting features emerging with the introduction of the layer-wise Reissner–Mindlin model are also highlighted, particularly with reference to coupling terms arising from shear effects.