Investigation on the Structure Strength and Stability of Ring Stiffened Cylindrical Shell With Long Compartment and Large Stiffener

With the increasing status of the sea, the research and manufacture of submersible vessel will be paid more attention. In order to enlarge the submergence depth and utilization efficiency of submersible vessel space, long compartment structures of high strength steels and in various forms are widely adopted. The strength problem of such structure is easy to be guaranteed, while the resulting stability problem is becoming more and more serious. For a ring-stiffened cylindrical shell structure with long compartment, one or two large stiffeners are used on the shell structure to ensure its overall stability. This paper studies the strength and stability of the long compartment cylindrical shell structure, with a special emphasis on the stability problems of overall long compartment structures and large stiffeners. The failure modes and critical load under deep water are analyzed by a theoretical method and also a finite element method. The formula for calculating the large stiffener of submersible vessel structure is derived based on the theory of elastic mechanics, and the defect and deficiency of the formula used in the current design specification is pointed out. The influence of large stiffener position and structure form on the critical pressure of submersible cylindrical shell structure is studied. The results of theoretical analysis and numerical simulation are also compared and discussed.