1. FIGS. 5-8. Compressive buckling stress coefficients for unpressurized circular cylinders these parameters, (3) establishment of t h e relationship between t h e critical buckling coefficient a n d t h e r/t ratio, a n d (4) performance of a statistical analysis on the test d a t a t o determine design curves. T h e reasoning behind t h e choice of parameters has already been given.
2. Shown in Figs. 5-8 are 252 experimental values of the critical buckling coefficient from t h e tests of twelve investigations. T h e discrepancy between theory a n d test is clearly shown in these Figures. However, t h e general trend of t h e test points follows t h e theoretical shape of t h e curve quite well. Batdorf, Schildcrout, and Stein19have proposed semiempirical curves t o account for this discrepancy between test a n d theory. Curves a t t h e theoretical slope were faired through t h e test d a t a in the long cylinder range for several values of r/t on the assumption t h a t the r/t ratio is indicative of the initial imperfections. T h e analysis employed in the present paper is a refinement of this procedure which includes a statistical basis for t h e correlation between the buckling coefficient a n d t h e r/t ratio. This is accomplished b y replotting t h e buckling coefficient as a function of t h e r/t ratio. Once t h e relationship between t h e buckling coefficient a n d r/t is determined, the statistical analysis of step (4) is performed, and the design curves are drawn in terms of t h e theoretical parameters, Kca n d Z .
3. The Buckling of Thin Cylindrical Shells Under Axial Compression
4. A Theory for the Buckling of Thin Shells