Hull Failure Demonstrations Model Hull Buckling Demo - This video demonstrates buckling of stainless steel cylinders under external pressure. Composite Cylinder Buckling Demo - This video demonstrates buckling of Glass Fiber and Carbon Fiber cylinders under external pressure. General Instability Demo - This video addresses the collapse of ring-stiffened sewerage pipes under external pressure. When sewerage and other pipes are buried under ground, they can fail by buckling due to the effects of external pressure transmitted through the soil by large vehicles travelling above. To strengthen the sewerage pipes under the effects of external pressure, they are usually ring-stiffened. When this is done the vessels can fail bodily through general instability, where the entire ring-shell combination implodes inwardly. Opening Reinforcement A Discussion of Area Replacement Method in Opening Reinforcement Design Openings in ASME Code Pressure Vessels Using the ASME VIII-1 Nozzle F Factor (UG-37)