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Abstract: This Note presents a FFT based-method for obtaining the permeability of a periodic micro-porous medium. The periodic medium is constituted of a rigid solid matrix saturated by a viscous fluid. The flow obeys the Stokes equations and a slip condition at the surface of the rigid skeleton is considered. The permeability is obtained from the homogenization of periodic media and an extension of the FFT method used for composite elastic media. The incorporation of the slip condition is made through the introduction of an interphase between the fluid and the solid. The method of solution uses the classical expansion along Neumann series of the velocity field of the periodic problem and Green''s tensor in Fourier space. To cite this article: V. Monchiet et al., C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

Abstract: The aim of this study is to present a framework for the modeling of damage in continuous unsaturated porous geomaterials. The damage variable is a second-order tensor. The model is formulated in net stress and suction independent state variables. Correspondingly, the strain tensor is split into two independent thermodynamic strain components. The proposed framework mixes micro-mechanical and phenomenological approaches. On the one hand, the effective stress concept of Continuum Damage Mechanics is used in order to compute the damaged rigidities. On the other hand, the concept of equivalent mechanical state is introduced in order to get a simple phenomenological formulation of the behavior laws. Cracking effects are also taken into account in the fluid transfer laws. To cite this article: C. Arson, B. Gatmiri, C. R. Mecanique 337 (2009). [Copyright &y& Elsevier]

A self-consistent scheme is used in order to determine the permeability of a cracked porous medium. For weak values of the permeability of the uncracked porous matrix, it is found that the order of magnitude of the permeability increases beyond a critical threshold of the crack density parameter. In the framework of a micromechanical model, it is shown that both the evolution of crack opening and the crack propagation are controlled by Terzaghi''s effective stress which therefore captures the coupling between permeability and mechanical loading. To cite this article: L. Dormieux, D. Kondo, C. R. Mecanique 332 (2004). [Copyright &y& Elsevier]