Nonlinear Stability of Ring-Stiffened Prestressed Domes

Abstract

Stability of a newly proposed structural system, namely, the prebuckled or prestressed dome with ring stiffener, is investigated. The prestressed dome is different from traditional domes in that it is made by first elastically buckling shallow, straight radial members and then attaching them to their supports. A special-purpose algorithm devised to consider a staged construction method of the system using nonlinear finite-element models is implemented into the program named DOME3D. Stability of the prestressed dome with two different rise-to-span ratios is studied with a varying number of ring stiffeners. The study shows that the stiffened system is not vulnerable to loading imperfections leading to side-sway buckling. The stiffening methods increased the limit load by more than 100% and changed the buckling mode of the system. For some stiffener configurations, the behavior of the stiffened domes was similar to shell-like domes. The results showed that the stiffening system leads to significant increase in the strength-to-weight ratio of the novel type structure, and improvement in the overall stability behavior of the dome.