- Ugo Galvanetto, University Of Padua
- Bernhard A. Schrefler
Fractures in materials take place when stress and work are applied at the atomic level to break the bonds that hold atoms together. This process can be made extremely complicated by the simultaneous presence of various interacting fields: thermal, electrical, gravitational, elastic, fluid, … The macroscopic description of fracture phenomena is one of the greatest challenges facing computational mechanics and, in spite of a research effort of at least four decades, reliable computational tools are not yet available.
Computational methods based on classical continuum mechanics, such as the popular displacement version of the Finite Element Method, have been equipped with a series of ad hoc tools to deal with cracks. This is due to the fact that classical continuum mechanics does not admit discontinuities, so researchers have to devise special techniques that are to be applied wherever a crack grows. Some of these ad hoc methods include virtual crack closure technique, cohesive zone model, interface elements, element erosion, extended finite element method, phase field theory... Although all these techniques have produced a rich literature and interesting results, there are various concerns on their applicability and versatility, which stem from the nature itself of classical continuum mechanics.
In the last twenty years a new nonlocal continuum theory, Peridynamics, has been proposed in a way to provide a consistent framework for modeling discontinuities in solid materials. ‘Since peridynamics is compatible with discontinuities and long-range forces, modeling these features is a matter of finding the right material model and applying the same basic field equations everywhere. Peridynamics avoids the need for special techniques that are incompatible with the basic equations’ . However Peridynamics too has its own drawbacks:
- computational methods based on nonlocal theories usually require a bigger computational effort;
- the nonlocal peridynamic form of some force fields may not be available yet and that is a clear obstacle to the use of Peridynamics.
The purpose of this minisymposium is to stimulate an exchange of ideas among researchers working with various types of approach: classical ones equipped with ad hoc tools, non-local, coupled local-nonlocal, non-local for the solid mechanics field and local for other fields etc … It will include, among others, the following topics:
- 1. Thermo-mechanic fracture
- 2. Electro-mechanic fracture
- 3. Fracture in porous media
- 4. Fracking
- 5. Local/nonlocal coupling methods
- 6. Numerical techniques, discretization schemes, and software implementation for nonlocal models
- 7. Meshfree and particle methods
- 8. Application of boundary conditions in non-local methods
- 9. Theoretical and numerical analysis of nonlocal models and multiscale methods
- 10. Material failure and damage
- 11. Local-Nonlocal damage, nonlocal plasticity models
- 12. Nonlocal multiphysic approaches
- 13. Large 3D applications
- 14. Nonlocal modelling of corrosion
Papers on topics not included in the list, but in line with the theme of the symposium, are also welcome.
Key words: fracture, multiphysics problems, nonlocal models, local models, numerical analysis, multiscale modelling, local-nonlocal coupling methods.
 Bobaru, Florin ; Foster, John T ; Geubelle, Philippe H ; Silling, Stewart A; Bobaru, Florin ; Foster, John T; Silling, Stewart A ; Geubelle, Philippe H, Handbook of Peridynamic Modeling, 2017; Boca Raton: Chapman and Hall/CRC.