Publication Details |
Category | Text Publication |
Reference Category | Journals |
DOI | 10.1007/s00603-018-1569-z |
Document | Shareable Link |
Title (Primary) | Hydro-mechanical modeling of tunnel excavation in anisotropic shale with coupled damage-plasticity and micro-dilatant regularization |
Author | Parisio, F.; Vilarrasa, V.; Laloui, L. |
Source Titel | Rock Mechanics and Rock Engineering |
Year | 2018 |
Department | ENVINF |
Volume | 51 |
Issue | 12 |
Page From | 3819 |
Page To | 3833 |
Language | englisch |
Keywords | Tunnel excavation; Anisotropic damage-plasticity of shales; Hydro-mechanical coupling; Nuclear waste storage; Mont Terri URL; Excavation damaged zone; Opalinus Clay |
Abstract | The disposal of highly radioactive spent nuclear fuel in deep geological media will require excavating a large number of galleries in low-permeable rocks, altering initial rock integrity at the repository site. The FE tunnel excavated in Opalinus Clay at the Mont Terri Underground Research Laboratory (Switzerland) is a unique full-scale experiment to study this process. We conducted a numerical study of the excavation of the FE tunnel in a coupled hydro-mechanical finite element framework, employing an anisotropic plasticity coupled with damage constitutive model. A second gradient of dilatancy formulation is employed to avoid spurious mesh-dependent behavior originating from the softening of the coupled damage-plasticity model. The approach is validated by comparing numerical predictions and in situ observations during and after tunnel excavation in terms of displacements, pore water pressure evolution and degradation of elasticity. Mechanical parameters are calibrated using laboratory experiments and values available in the literature. The model well reproduces the coupled hydro-mechanical processes induced by excavation, giving a good agreement between numerical predictions and experimental in situ monitoring data. Furthermore, the evolution of the excavation damaged zone is correctly predicted. Thus, this modeling approach is suitable for the purpose of simulating tunnel excavation in low-permeable anisotropic quasi-brittle shales. |
Persistent UFZ Identifier | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=21268 |
Parisio, F., Vilarrasa, V., Laloui, L. (2018): Hydro-mechanical modeling of tunnel excavation in anisotropic shale with coupled damage-plasticity and micro-dilatant regularization Rock Mech. Rock Eng. 51 (12), 3819 - 3833 10.1007/s00603-018-1569-z |