Homogenization of a thin linear elastic plate reinforced with a periodic mosaic of small rigid plates
Amartya Chakrabortty, Georges Griso, Julia Orlik
TL;DR
This work derives a rigorous two-dimensional limit model for a thin Kirchhoff-Love plate reinforced by a periodic mosaic of rigid inclusions, under simultaneous homogenization and dimension reduction with vanishing thickness and periodicity. By decomposing displacements to separate KL bending from rigid constraints and employing ${\cal Q}_1$-interpolations and rescaled unfolding operators, the authors obtain uniform Korn-type estimates and unfold the 3D problem to a pair of decoupled 2D plate problems. The homogenized limit is governed by a two-field variational inequality with an effective tensor $\mathcal{A}^{(\alpha)}$ computed from cell problems, yielding a strong, well-posed macroscopic model with explicit correctors and recovery sequences. The results provide a detailed, multiscale framework for designing and analyzing thin composite plates with rigid periodic inclusions, including NPC considerations and asymptotic energy convergence.
Abstract
In the framework of linearized elasticity, we study thin elastic composite plates with thickness $δ$. The plates contain small, rigid rectangular plates distributed periodically along $\varepsilon$. Between two neighboring rigid plates is an elastic beam with thickness $δ< \varepsilon/3 < 1$. Through a simultaneous process of homogenization and dimension reduction, we obtain the limit model. Our analysis yields Korn-type inequalities adapted to the rigid-elastic geometry of the structure and provides a precise characterization of the limit deformation and displacement fields. In the $2$D limit problem, the bending is the sum of two functions, each depending on only one variable. This is due to the fact that the mixed derivatives of the outer-plane displacement vanish. Finally, the limiting 2D problem is two decoupled plates or strips, each one with just three degrees of freedom: shear along the strip axis, the cross-contraction (-extension), and the cross-bending. The corresponding correctors are defined in the same way in the periodicity cell. In the linearized setting, all the correctors are decomposed.
