In this paper we prove the relaxation theorem in micropolar elasticity and use it, together with the semicontinuity theorem, to justify lower-dimensional models of rods (and plates) by means of Γ-convergence starting from general energy functionals. The internal energy density is assumed to be continuous and satisfies some growth and coercivity conditions. In particular, we apply these results to derive a rod model starting from quadratic isotropic energy density function of a cylindrical three-dimensional micropolar body.
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