We show that nonlinearly elastic plates of thickness h→0 with an
ε-periodic structure such that ε−2h→0 exhibit
non-standard behaviour in the asymptotic two-dimensional reduction from
three-dimensional elasticity: in general, their effective stored-energy density
is "discontinuously anisotropic" in all directions. The proof relies on a new
result concerning an additional isometric constraint that deformation fields
must satisfy on the microscale.Comment: 35 page