Imperfection sensitivity of conical shells

The sensitivity of isotropic conical shells to imperfection is considered, via the initial postbuckling analysis, on the basis of three different shell theories: Donnell's, Sanders's, and Timoshenko's. The conical shell was chosen as a representative case exhibiting the entire range of imperfection sensitivity. The procedure involves nonlinear partial differential equations, which are converted into a sequence of three linear sets. The latter are solved with the variables expanded in Fourier series in the circumferential direction and in finite differences in the axial directions. A general code is developed and used in studying the effect of higher exactness of the shell theory on the sensitivity behavior and in parametric analyses of the sensitivity of conical shells, especially with respect to the cone semivertex angle.