Homogenized elastic–viscoplastic behavior of plate-fin structures with two pore pressures

Abstract

We investigate the homogenized elastic–viscoplastic behavior of plate-fin structures subjected to two pore pressures, p1 and p2. The plate-fin structures considered are assumed to be periodic and composed of metallic materials. Hill's macrohomogeneity equation is used to show three special cases in which one of p1, p2 or pm (the mean of p1 and p2) entirely affects the homogenized viscoplastic behavior in the steady state. To verify the three special cases, we perform FEH (finite element homogenization) analysis of an ultrafine plate-fin structure subjected to p1 and p2, for which two base metals with different strain-rate sensitivities are considered. It is demonstrated that the three special cases typically occur under uniaxial tension and compression in the stacking direction, depending on the strain-rate sensitivity of the base metals. It is further shown that a macromaterial model reproduces well the homogenized stress–strain relations attained in the FEH analysis if p1, p2 or pm is entered for Terzaghi׳s effective stress in the viscoplastic equation in the macromaterial model.