Quasi-isotropic Biot’s Tensor for Anisotropic Porous Rocks: Experiments and Micromechanical Modelling

Cong Hu (1) , Éric Lemarchand (2) , Luc Dormieux (2) , Frédéric Skoczylas (3)

1 Shandong Provincial Key Leological Engineering, Changzhou, China
2 NAVIER UMR 8205 - Laboratoire Navier
3 LaMcube - Laboratoire de Mécanique, Multiphysique, Multiéchelle - UMR 9013

Several experimental studies, carried out on anisotropic rocks, have evidenced that even though strains, due to isotropic loading and/or internal fluid pressure, are strongly anisotropic, the resulting Biot’s tensor is almost isotropic. Those results were found on two different rocks: a clay rock (France—Bure argillite) and a sandstone from the Vosges region (France). Such (a priori) surprising results led us to develop micromechanical modelling in which anisotropy comes either from an anisotropic solid matrix (and isotropic pore space) or from an anisotropic pore space (and isotropic solid matrix). The obtained results have shown that for both cases the Biot’s tensor is virtually isotropic or presents a very weak anisotropy. This unambiguously supports the fact that a strongly anisotropic porous material is compatible with experimental measurements of isotropic (or quasi isotropic) Biot’s tensor

Mots clés: Anisotropic rock; Biot’s tensor; Poromechanical coupling; Micromechanical model

Domaines: Matériaux

Cong Hu, Éric Lemarchand, Luc Dormieux, Frédéric Skoczylas. Quasi-isotropic Biot’s Tensor for Anisotropic Porous Rocks: Experiments and Micromechanical Modelling. Rock Mechanics and Rock Engineering, In press, ⟨10.1007/s00603-020-02147-7⟩. ⟨hal-02745830⟩