Experimental and numerical studies on the elasto-plastic buckling response of cylindrical shells with spigot support under axial compression

In this work, an experimental and numerical methodology is proposed to study the elasto-plastic buckling response of thin cylindrical shells with spigot support under axial compression. A multi-3D digital image correlation system is used to measure the geometrical imperfections as well as the buckling response of the shell. Further, a coordinate measuring machine is employed to measure the edge loading imperfections of the shell. Next, interpolation methods are employed to transfer the measured imperfections to a finite element (FE) model. The effect of interference between the spigot and shell on the nonlinear buckling response of the shell is studied. The numerical results of FE models embedded with the measured edge and radial imperfections are compared with the experimental response. This study emphasizes the importance of including geometrical/loading imperfections for accurately estimating the buckling load of cylindrical shells used in launch vehicle applications.