Geometrically non-linear damage interface based on regularized strong discontinuity

The contribution of this paper concerns the fracture modelling of an interface with a xed internal material surface in the context of geometrically non-linear kinematics. Typical applications are composite laminates and adhesive=frictional joints in general. In the model development, a key feature is the concept of regularized strong discontinuity, which provides a regular deformation gradient within the interface. The deformation gradient within the interface is formulated in a multiplicative structure with a continuous part and a discontinuous part, whereby the interface deformation is interpreted as a transformation between the material damaged con guration and the actual spatial con guration. In analogy with the continuum formulation of hyper-inelasticity, a constitutive framework is de ned for the relation between the induced material traction and the displacement jump vector, which are de ned on the material damaged interface con guration. Within this framework, a simple, but yet still representative, model for the delamination problem is proposed on the basis of a damage–plasticity coupling for the interface. The model is calibrated analytically in the large deformation context with respect to energy dissipation in mode I so that a prede ned amount of fracture energy is dissipated. The paper is concluded with a couple of numerical examples that display the properties of the interface