A simplified model for confined compression of granular materials is considered, which idealizes the collection of particles as a (central) force network. Applying an effective-medium procedure, an equation with micromechanically well-defined parameters is derived, which relates the applied pressure to the engineering strain of the powder during uniaxial compression. Despite the simplicity of the model, comparison with experimental data for mm-sized spherical granules indicates that this equation is able to satisfactorily predict the overall compression profile from single-particle data. (C) 2009 Elsevier B.V. All rights reserved.