A quasi-static interface damage model with cohesive cracks: SQP–SGBEM implementation

A quasi-static model for crack-mode sensitive interface damage with linearly elastic bodies at small strains is developed. It invokes a cohesive type response of the interface interpreted as a thin layer of an adhesive. The damage model is defined with the aim to obtain stress–strain relations in the cohesive zone typically employed in engineering interface-models. The weak solution of the problem is sought numerically by a semi-implicit time-stepping procedure which uses recursive double minimization in displacements and damage separately. The spatial discretization is performed by the symmetric Galerkin boundary-element method. Quadratic and sequential quadratic programming are implemented to resolve each partial minimization of the recursive scheme in the computation of the time-discretized solutions. Sample 2D numerical examples demonstrate applicability of the model as well as efficiency of the SGBEM and convex programming numerical implementations.