[en] A zone with significant irreversible processes and significant changes in flow and transport properties is expected to be formed after underground excavations. The perturbation of the excavation could lead to a significant increase of the permeability, related to diffuse and/or localized crack proliferation in the material. The main objective of the study is to model these processes at large scale in order to assess their impacts on the performance of radioactive waste geological repositories. This paper concerns more particularly the hydro-mechanical modeling of a long term dilatometer experiment performed in Mont Terri Rock Laboratory in Switzerland. The proposed model defines the permeability as a function of the aperture of the cracks that are generated during the excavation. With this model, the permeability tensor becomes anisotropic. These developments are validated with the results of the experiment.
Disciplines :
Civil engineering
Author, co-author :
Levasseur, Séverine ; Université de Liège - ULiège > Département Argenco : Secteur GEO3 > Géomécanique et géologie de l'ingénieur
Collin, Frédéric ; Université de Liège - ULiège > Département Argenco : Secteur GEO3 > Géomécanique et géologie de l'ingénieur
Frieg, Bernd; NAGRA
Charlier, Robert ; Université de Liège - ULiège > Département Argenco : Secteur GEO3 > Géomécanique et géologie de l'ingénieur
Language :
English
Title :
Hydro-mechanical modeling of damage due to underground excavation in hardened clay
Publication date :
2009
Event name :
ComGeo I
Event organizer :
Prof. Gyan N. Pande, Prof. Stan Pietruszczak, Prof. Claudio Tamagnini, Prof. Richard Wan
Event place :
Juan-les-Pins, France
Event date :
29 avril au 1er mai 2009
Audience :
International
Main work title :
Computational Geomechanics
Editor :
Pietruszczak, Stan
Pande, Gyan
Tamagnini, Claudio
Wan, Richard
Publisher :
IC2 E International Centre for Computational Engineering, Rhodes, Greece
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