Collapse pressure of randomly corroded stiffened spherical shell

Abstract

Aged spherical shells are consistently subject to corrosion, which can cause a dramatic decrease in loading capacity. Spherical shells can be subjected to large forces, or the size of the shell is required. On the basis of this research background, stiffened spherical shells (SSSs), which are set circular stiffeners set on the inner surface of the shell, is proposed. To quantify the influence of corrosion on the collapse pressure of the SSSs, stochastic numerical analysis is performed. The influences of tc/t, Dc/D, ts, hs, geometrical imperfection, and the number of stiffeners on the collapse pressure are revealed. This study investigates the constant and random tc/t. The formula that predicts the reduction factor of collapse pressure for the SSSs with random pitting corrosion is proposed. The maximum error is less than 14%. Results indicate that the proposed method has high accuracy in predicting the reduction factor corresponding to the pitting corrosion. The proposed analytical method is applicable for constant and random tc/t. The work presented in this paper can provide a reference for the efficient improvement of the collapse pressure of spherical shells and evaluating the collapse pressure of the existing SSSs.