Linear and nonlinear elastic buckling of stereolithography resin egg-shaped shells subjected to external pressure

This study explored the elastic buckling of egg-shaped shells made of stereolithography resin. The shells had identical nominal geometry parameters with the thickness of 2 mm, the major axis of 232 mm, and the minor axis of 160 mm, respectively. Five near-perfect laboratory-scale models were fabricated using stereolithography appearance (SLA), a rapid prototyping technique. Each model was scanned by a three-dimensional optical scanner, measured using a micrometer, and tested in a pressure chamber. The buckling behaviours of egg-shaped shells with deterministic geometric imperfections were experimentally, analytically, and numerically analysed. The perfect egg-shaped shell was also compared with the fabricated egg-shaped models. A good agreement among them was obtained. The remarkable experimental results of egg-shaped shells were presented in this paper by using 3D printing technologies, which shows the high machining accuracy of 3D printing technologies and provides a new solution for the limitation of experimental study into non-typical shells of revolution. Also, the study could provide a new non-typical shell structure and its stability evaluation approach for space vehicles, pressure tanks, and pressure hulls.