Stiffness Analysis of Sheet Metal Shells under Concentrated Loads

The objective of this paper is to study the applicability of the finite element method in calculating both small and large deflections of sheet metal shells subject to concentrated loads in the elastic range. In the small deflection case, three types of elements -- the Hsieh-Clough-Tocher triangular plate element, the Felippa quadrilateral plate element, and the Dupuis triangular shell element -- are used to calculate the stiffness of two simple panels (a sectional circular cylinder and a paraboloid) and a spherical cap. The calculated results show that all three elements give solutions converging to the exact shell solutions. For large deflections, load-displacement curves of the spherical cap are computed for deflections up to three shell thicknesses using the Dupuis element.