Applications of a new computational model of interface and phase-field fracture

Resumo

Computational analysis of fracture in multi-domain structures is considered so that cracks may appear in
material bulks and also along material interfaces. The proposed computational model introduces two independent
damage parameters relying on representation of rupture by mechanical damage theory. One of them being pertinent
to the interface considering it as a negligibly thin adhesive layer of a contact zone between structural components.

The arising interface cracks are supposed to appear so that cohesive zone models with general stress-strain relation-
ships are implemented. The other damage parameter defined for the bulks uses the theory of phase-field fracture

which causes elastic properties degradation only in a narrow material strip that forms a diffused crack. Both of
these damaging schemes are expressed in terms of a quasi-static energy evolution process. Having such an energy

formulation, the proposed computational approach is introduced in a variational form. The solution evolution be-
ing approximated by a semi-implicit time stepping procedure related to a separation of deformation and damage

variables. The deformation and damage solutions at each instant being obtained by non-linear programming algo-
rithms implemented together within a MATLAB finite element code. The numerical simulations with the model

include an analysis of fibre separation arising in a fibre-reinforced composite material.