Experimental characterization and numerical modelling of fracture processes in granite

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Francesco Parisio - , Helmholtz-Zentrum für Umweltforschung (UFZ) (Autor:in)
  • Ali Tarokh - , University of Illinois at Urbana-Champaign (Autor:in)
  • Roman Makhnenko - , University of Illinois at Urbana-Champaign (Autor:in)
  • Dmitri Naumov - , Helmholtz-Zentrum für Umweltforschung (UFZ) (Autor:in)
  • Xing Yuan Miao - , Professur für Angewandte Umweltsystemanalyse (gB/UFZ), Helmholtz-Zentrum für Umweltforschung (UFZ) (Autor:in)
  • Olaf Kolditz - , Professur für Angewandte Umweltsystemanalyse (gB/UFZ), Helmholtz-Zentrum für Umweltforschung (UFZ) (Autor:in)
  • Thomas Nagel - , Helmholtz-Zentrum für Umweltforschung (UFZ), Trinity College Dublin (Autor:in)

Abstract

Failure in brittle rock happens because micro-cracks in the crystal structure coalesce and form a localized fracture. The propagation of the fracture is in turn strongly influenced by dissipation in the fracture process zone. The classical theory of linear elastic fracture mechanics falls short in describing failure when the dissipation in the fracture process zone is non-negligible; thus, a non-linear theory should be employed instead. Here we present a study in which we explore the characteristics of the fracture process zone in granite. We have combined fracture tests on Adelaide black granite with acoustic emission detection and finite element analyses by using a non-local integral plastic-damage constitutive theory. We have further employed the theory of configurational mechanics to support our interpretation of the evolution of the fracture process zone with strong energy-based arguments. We demonstrate that the size of the fracture process zone is non-negligible and dissipative phenomena related to micro-cracking play an important role. Our results indicate this role should be assessed case by case, especially in laboratory-sized analyses, which mostly deflect from theories of both size-independent plasticity and linear elastic fracture mechanics. When strong non-linearities occur, we show that fracture energy can be correctly computed with the help of configurational mechanics and that complex numerical simulation techniques can substantially facilitate the interpretation of experiments designed to highlight the dominant physical mechanisms driving fracture.

Details

OriginalspracheEnglisch
Seiten (von - bis)102-116
Seitenumfang15
FachzeitschriftInternational journal of solids and structures
Jahrgang163
PublikationsstatusVeröffentlicht - 15 Mai 2019
Peer-Review-StatusJa

Schlagworte

Schlagwörter

  • Crack-tip plasticity, Finite elements, Fracture mechanisms, Mechanical testing, OpenGeoSys