Design charts for clamped orthotropic plates

This paper focuses on the application of orthotropic plate bending theory, particularly of Schade’s design curves, to the scantlings assessment of deck primary supporting members in absence of pillars. Preliminarily, a review of Schade’s works is presented, paying attention to the design curves relative to the plate with all edges clamped, that are almost totally incomplete. Therefore a numerical solution for the clamped orthotropic plate equation is obtained. The Ritz method is adopted, expressing the vertical displacement field by a double cosine trigonometric series, whose coefficients are determined by solving a linear equation system. Several design curves are proposed for different values of the torsional parameter in a range comprised between 0 and 1, as functions of the virtual aspect ratio comprised between 1 and 8, in order to estimate the asymptotic behaviour of the orthotropic plate for high values of the above mentioned parameter. Finally, a numerical application relative to the deck of a fast ferry is presented.