Study of poroelasticity material coefficients as response of microstructure

Using an asymptotic homogenization method, the effect of the porous medium microstructure on the values of poroelastic coefficients is studied in this paper. First, the Blot's poroelasticity theory and general relations linki ng the macroscopic poroelastic coefficients with the averaged micromechanic al solutions are recalled. Considering a variational formulation of appropr iate boundary values problems stated for the representative volume element, microstructural parameters affecting the Values of poroelastic coefficient s are identified. In order to clarify specific roles of some relevant micro structure parameters, numerical investigations for some simplified pores ge ometries are presented. The numerical results obtained clearly show a stron g dependence of the poroelastic coefficients on the internal geometry of po res as well as on the global porosity of the medium. In the last part, base d on the micromechanics analysis, the definition of initial plastic yield c ondition for saturated porous media is introduced and a new interpretation of the effective stress concept in inelastic domain is proposed. Copyright (C) 2000 John Wiley & Sons, Ltd.