The fundamental parameter method is applied to the stress integration in the case of the elasto-plastic deformation of the material at the combined reinforcement defined by the von Mises creep condition. Next, the increment stress at strains determined in the general 3-D strain case as well as under plane-state shell and beam stress conditions is determined. Expressions are also deduced concerning the constituent tangent elastoplastic matrix. Some numerical examples illustrate the efficiency and simplicity of the proposed numerical process.