Evaluation of Bead-Stiffened Metal Panels

Abstract

Potential weight efficiency for bead-stiffened panels has been demonstrated through fabrication and testing. Theoretically optimum design concepts were identified, and small specimens were tested under combined compression, shear, and bending to determine local buckling failure loads and to verify theory. Large optimized panels were then designed and tested under combined loads. Correlation of test data for large circular tubular panels with theory was conservative and consistent, and indicated reliable and acceptable design theory. Tests of fluted tubular panels indicated general instability failures at loads far below the design values because of nonlinear distortions. Further study of the fluted tubular configuration will be required if its potential weight efficiency is to be attained. Nomenclature F^= compression yield stress N x = panel axial compression load Nxy = panel shear load p = pressure q = heating rate R B ,R C ,R S = ratios of actual stress to critical stress for bending, compression, and shear, respectively T = temperature t = rime p = density