User login

Navigation

You are here

Revisiting Nucleation in the Phase-Field Approach to Brittle Fracture

Oscar Lopez-Pamies's picture

Twenty years in since their introduction, it is now plain that the regularized formulations dubbed as phase-field of the variational theory of brittle fracture of Francfort and Marigo (1998) provide a powerful macroscopic theory to describe and predict the propagation of cracks in linear elastic brittle materials under arbitrary quasistatic loading conditions. Over the past ten years, the ability of the phase-field approach to also possibly describe and predict crack nucleation has been under intense investigation. The first of two objectives of this paper is to establish that the existing phase-field approach to fracture at large — irrespectively of its particular version  cannot possibly model crack nucleation. This is so because it lacks one essential ingredient: the strength of the material.

The second objective is to amend the phase-field theory in a manner such that it can model crack nucleation, be it from large pre-existing cracks, small pre-existing cracks, smooth and non-smooth boundary points, or within the bulk of structures subjected to arbitrary quasistatic loadings, while keeping undisturbed the ability of the standard phase-field formulation to model crack propagation. The central idea is to implicitly account for the presence of the inherent microscopic defects in the material  whose defining macroscopic manifestation is precisely the strength of the material  through the addition of an external driving force in the equation governing the evolution of the phase field. To illustrate the descriptive and predictive capabilities of the proposed theory, the last part of this paper presents sample simulations of experiments spanning the full range of fracture nucleation settings.

https://www.sciencedirect.com/science/article/pii/S0022509620302623

Comments

Ashkan_Golgoon's picture

Thanks Oscar for sharing this nice paper. 

Ashkan,

Subscribe to Comments for "Revisiting Nucleation in the Phase-Field Approach to Brittle Fracture"

More comments

Syndicate

Subscribe to Syndicate