Application of the orthotropic plate theory to garage deck dimensioning

This paper focuses on the application of orthotropic plate bending theory to stiffened plating. Schade’s design charts for rectangular plates are extended to the case where the boundary contour is clamped, which is almost totally incomplete in the afore mentioned charts. A numerical solution for the clamped orthotropic plate equation is obtained. The Rayleigh-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. Numerical results are proposed as design charts similar to those ones by Schade. In particular, each chart is relative to one of the non-dimensional coefficients identifying the plate response; each curve of any chart is relative to a given value of the torsional parameter, in a range comprised between 0 and 1, and is function of the virtual aspect ratio, comprised between 1 and 8, so that the asymptotic behaviour of the orthotropic plate for high values of the above mentioned parameter is clearly shown. Finally, some numerical applications relative to ro-ro decks are presented, in order to evaluate the accuracy and the capability of the proposed technique for stiffened deck analysis. Obtained results are examined in order to draw a usable procedure for dimensioning deck primary supporting members, taking into account the interaction of the two orthogonal beam sets.