Interface and phase-field dynamic quasi-brittle fracture of solids under tension or compression

A computational dynamic fracture model for multimaterials is described to provide crack-mode dependence including particular treatment when the load causes compression. The model also distinguishes between fracture in material and along interfaces. The former is simulated by the theory of phase-field fracture which causes material damage to occur in a thin material band introducing regularised cracks. The latter considers the interface to be a thin damageable adhesive layer with its own rule of degradation. In both cases internal variables are introduced for modelling. The computational approach is rendered from dynamic evolution equations based on the Hamilton principle adapted for dissipative systems. The calculations use a staggered time-stepping procedure and sequential quadratic programming algorithms together with a MATLAB finite element in-house code.