Finite element approximation of free vibration of folded plates

In this paper a finite element approximation of the free vibration of folded plates is studied. Naghdi model, including bending, shear and membrane terms for the plate, is considered. Quadrilateral low order MITC (Mixed Interpolation Tensorial Component) elements are used for the bending and shear effect, coupled with standard quadratic elements enriched with a drilling degree of freedom for the membrane term. Convergence properties and optimal order error estimates are proved. Numerical examples, showing the good behavior of the method, are presented for one and two folded plates with different thickness and crank angles.