Plate vibration with arbitrarily oriented stiffeners based on Mindlin-Engesser formulation

This paper investigates the free vibration analysis of moderately thick plates with arbitrarily oriented stiffeners. Formulation of the energy functional incorporates the Mindlin theory to account for the effects of shear deformation and rotary inertia of plates, and the Engesser theory is used to account for the shear deformation of stiffeners with the inclusion of torsion effect. The Ritz minimization procedure with a set of pb-2 shape functions is employed for solution. Numerical investigations using stiffened plates of various shapes have been undertaken to illustrate the applicability and versatility of this procedure. A detailed parametric study of the effects of geometric parameters on the vibratory characteristics is reported. In the paper, the simplicity and accuracy of the proposed solution method are highlighted.