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Identification of scale-independent material parameters in the relaxed micromorphic model through model-adapted first order homogenization

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 نشر من قبل Marco Valerio d'Agostino
 تاريخ النشر 2019
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Patrizio Neff




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We rigorously determine the scale-independent short range elastic parameters in the relaxed micromorphic generalized continuum model for a given periodic microstructure. This is done using both classical periodic homogenization and a new procedure involving the concept of apparent material stiffness of a unit-cell under affine Dirichlet boundary conditions and Neumanns principle on the overall representation of anisotropy. We explain our idea of maximal stiffness of the unit-cell and use state of the art first order numerical homogenization methods to obtain the needed parameters for a given tetragonal unit-cell. These results are used in the accompanying paper [16] to describe the wave propagation including band-gaps in the same tetragonal metamaterial.



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