Homogenization-based Constitutive Models for Two-dimensional Viscoplastic Porous Media with Evolving Microstructure
نویسندگان
چکیده
In this study, we present a model based on the “second-order” nonlinear homogenization method for estimating the macroscopic response and the evolution of microstructure in two-dimensional viscoplastic porous media. The estimates of the new model are compared with unit cell finite element calculations and the earlier “variational” nonlinear homogenization method. The three methods are compared for uniaxial tension and compression, as well as for simple shear loadings. The “secondorder” model is found to improve on the earlier “variational” method by being in good agreement with the finite element results.
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