Imperfection-sensitivity of a wide integrally stiffened panel under compression

Abstract The initial post-buckling behaviour is determined for an integrally stiffened wide panel under compression. Overall buckling of the panel as a wide Euler column and local buckling of the plates between the stiffeners are considered. Designing the panel so that the critical bifurcation load is the highest possible for a given amount of material per unit width tends to lead to a structure in which Euler-type buckling and local buckling occur simultaneously. It is shown that such a panel is very sensitive to geometrical imperfections. Thus, the critical bifurcation load cannot be reached in a practical structure and the two-mode design may not be optimal.