The importance of Thermo-Hydro-Mechanical couplings and microstructure to strain localization in 3D continua with application to seismic faults. Part II: Numerical implementation and post-bifurcation analysis - École des Ponts ParisTech Accéder directement au contenu
Article Dans Une Revue Journal of the Mechanics and Physics of Solids Année : 2018

The importance of Thermo-Hydro-Mechanical couplings and microstructure to strain localization in 3D continua with application to seismic faults. Part II: Numerical implementation and post-bifurcation analysis

Hadrien Rattez
  • Fonction : Auteur
Ioannis Stefanou
Jean Sulem

Résumé

In this paper, we study the phenomenon of localization of deformation in fault gouges during seismic slip. This process is of key importance to understand frictional heating and energy budget during an earthquake. A infinite layer of fault gouge is modeled as a Cosserat continuum taking into account Thermo-Hydro-Mechanical (THM) couplings. The theoretical aspects of the problem are presented in the companion paper (Rattez et al., 2017a), together with a linear stability analysis to determine the conditions of localization and estimate the shear band thickness. In this Part II of the study, we investigate the post-bifurcation evolution of the system by integrating the full system of non linear equations using Finite Elements. The problem is formulated in the framework of Cosserat theory. It enables to introduce information about the microstructure of the material in the constitutive equations and to regularize the mathematical problem in the post-localization regime. We emphasize the influence of the microstructure and of the softening law on the material response and the strain localization process. The weakening effect of pore fluid thermal pressurization induced by shear heating is examined and quantified. It enhances the weakening process and contributes to the narrowing of shear band thickness. Comparisons with the linear analysis exhibit that when the perturbed field of shear deformation dominates, the estimation of the shear band thickness obtained from linear stability analysis differs from the one obtained from the finite element computations, demonstrating the importance of post-localization numerical simulations.
Fichier principal
Vignette du fichier
Rattez et al._2018_Thermo-hydro mechanical couplings and strain localisation in 3D continua with microstructure. Part II Numerical impl.pdf (1.96 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-01728837 , version 1 (12-03-2018)

Identifiants

Citer

Hadrien Rattez, Ioannis Stefanou, Jean Sulem, Manolis Veveakis, Thomas Poulet. The importance of Thermo-Hydro-Mechanical couplings and microstructure to strain localization in 3D continua with application to seismic faults. Part II: Numerical implementation and post-bifurcation analysis. Journal of the Mechanics and Physics of Solids, 2018, ⟨10.1016/j.jmps.2018.03.003⟩. ⟨hal-01728837⟩
123 Consultations
306 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More