The integral approach to nonlocal ductile damage is developed to enable numerically stable and physically reasonable simulations of crack initiation and propagation in metals. A previously proposed phenomenological model of finite strain plasticity is delocalized through introducing a nonlocal evolution equation for porosity. In the new model, the strain localization is controlled by at least one internal length parameter, thus avoiding unphysical strain localization into a zero thickness layer. For numerical tests, meshless smoothed particle simulations of crack propagation in a compact tension specimen are carried out. The new nonlocal model's performance is analysed in terms of the force–displacement curves, critical stress intensity factors, energy dissipation during crack propagation, and geometry of the damaged zone. The impact of the delocalization procedure on structural strength under mode-I fracture is clarified: (i) isotropic and anisotropic delocalization procedures are considered; (ii) the averaging operator is applied both on the reference and current configurations; (iii) damage–continuity interaction is introduced to reduce unphysical spreading of damage.
Предметные области OECD FOS+WOS
- 2.03.IU ИНЖЕНЕРИЯ, МЕХАНИЧЕСКАЯ
- 2.03.PU МЕХАНИКА
- 2.05.PM МАТЕРИАЛОВЕДЕНИЕ, МУЛЬТИДИСЦИПЛИНАРНОЕ