The initial buckling of a long and slightly bowed panel under combined shear and normal pressure

Abstract

Recent American experimental work has suggested that the resistance to buckling of wing skin panels under compression or shear loads is improved by aerodynamic suction. A complete theoretical analysis of this problem is very difficult, because compression load necessarily involves the consideration of post-buckling behaviour. An approach is made in this report by considering the restricted problem of the initial buckling of a long, thin and slightly bowed panel under combined shear and normal pressure. The theoretical values of the initial shear buckling stress, which agree well with American experimental values increase with both pressure and curvature; the wavelength of the buckles also increases with pressure, but decreases with curvature. The difference between the buckling stresses for simply supported and clamped edges is considerable for a flat panel under shear alone but decreases rapidly with curvature and pressure, thus making the indeterminacy of practical edge conditions of less importance.