This article is concerned with tortuosity effects in coupled transport and mechanical properties of fractured geomaterials. Experimental results on confined fractured argillite samples are presented in terms of (1) progressive fracture reclosure and (2) fracture in plane permeability evolution, both depending upon confinement intensity. The observed non-linear mechanical response (fracture reclosure law) is physically interpreted as the progressive reclosure of local pores. The weak correlation between mechanical and hydraulic measurements is attributed to tortuosity effects which enhance the initial decrease of the permeability. The classical Self-Consistent scheme is herewith developed to qualitatively and quantitatively give theoretical basis likely to account for these tortuosity effects on permeability evolution.