Deformation and stability studies of thin-walled domes under uniform external pressure

Abstract

Fifty hemiellipsoidal domes were cast in solid urethane plastic, with profiles which varied from oblate to prolate shapes.The domes were subjected to external hydraulic pressure in a test tank and tested to failure. All the domes appeared to fail through elastic instability, the oblate shapes failing axisymmetrically, and the prolate shapes failing asymmetrically in a lobar manner.The theoretical analysis was carried out via the finite element method, and stiffness matrices were developed for an axisymmetric element of constant meridional curvature. The element was capable of being applied to axisymmetric deformation or axisymmetric and asymmetric instability, and it was generated numerically.