Micromechanical Approach to the Effective Poroelastic Behavior of Jointed Rock Masses under One-Dimensional Consolidation and Finite Element Implementation

Resumo

A micromechanics-based formulation of the macroscopic behavior of saturated jointed rocks regarded
as homogenized anisotropic poroelastic media is presented. At the material level, the rock matrix forming the
skeleton phase of the porous medium is assumed to be linear elastic, whereas the crosscutting joints stand for
the porous space and are viewed as planar interfaces endowed with a specific generalized poroelastic behavior.
The effective anisotropic poroelastic properties, including the homogenized drained elastic stiffness tensor C, Biot
tensor B, Biot modulusM, as well as the permeability tensor K of the jointed medium are derived. At the structure
level, the consolidation problem of a jointed rock layer is addressed in a one-dimensional setting with anisotropic
flow conditions introduced by joints orientations. For verification purpose, the analytical predictions derived from
the analysis are compared with finite element solutions implementing the effective constitutive state equations,
thus emphasizing that the analytical predictions can be viewed as reference solutions.