Variational regularization of damage models based on the emulated RVE
- verfasst von
- S. Schwarz, Philipp Junker, K. Hackl
- Abstract
Material models exhibiting softening effects due to damage or localization share the problem of leading to ill-posed boundary value problems that lead to physically meaningless, mesh-dependent finite element results. It is thus necessary to apply regularization techniques that couple local behavior, described, e.g., by internal variables, at a spatial level. The common way to do this is to take into account higher gradients of the field variables, thus introducing an internal length scale. In this paper, we suggest a different approach to regularization that does not make use of any nonlocal enhancement like the inclusion of higher gradients or integration over local sub-domains nor of any classical viscous effects. Instead we perform an appropriate relaxation of the (condensed) free energy in a time-incremental setting which leads to a modified energy that is coercive and satisfies quasiconvexity in an approximate way. Thus, in every time increment a regular boundary value problem is solved. The proposed approach holds the same advantage as other methods, but with less numerical effort. We start with the theoretical derivation, discuss a rate-independent version of the proposed model and present details of the numerical treatment. Finally, we give finite element results that demonstrate the efficiency of this new approach.
- Organisationseinheit(en)
-
Institut für Kontinuumsmechanik
- Typ
- Artikel
- Journal
- Continuum Mechanics and Thermodynamics
- Band
- 33
- Seiten
- 69-95
- Anzahl der Seiten
- 27
- ISSN
- 0935-1175
- Publikationsdatum
- 01.2021
- Publikationsstatus
- Veröffentlicht
- Peer-reviewed
- Ja
- ASJC Scopus Sachgebiete
- Allgemeine Materialwissenschaften, Werkstoffmechanik, Allgemeine Physik und Astronomie
- Elektronische Version(en)
-
https://doi.org/10.1007/s00161-020-00886-0 (Zugang:
Offen)
