ABSTRACT
Existing methods for improving the overall stability of ring-stiffened cylindrical shell are use of extra-large stiffeners and reduction of the length of compartment, etc. However, the overall stability of the ring-stiffened cylindrical shell of some dimensions cannot be effectively improved using these methods. This phenomenon is usually referred to as the abnormal characteristics. Therefore, it is significant to study the abnormal characteristics of pressure hull when the overall stability of the ring-stiffened cylindrical shell is being evaluated. In this paper, the instability equation of a ring-stiffened cylindrical shell under uniform pressure is presented based on the Ritz method. Then, the effect of improving the overall stability by adding intermediate ring-stiffener, deceasing stiffener-spacing and increasing plate thickness are discussed with the theoretical method. Finally, the feasibility of adding longitudinal and transverse stiffeners to improve the overall stability of cylindrical shell structure with abnormal characteristics and the influence of some related structural parameters on the overall stability are discussed.
