Postbuckling Behavior of Inelastic Inextensional Rings Under External Pressure

This paper deals with the problem of predicting the postbuckling configuration of a thin, inextensional, inelastic ring under external pressure. Previous work has shown that the postbuckling configuration of such a ring is unstable up to the point where the first two diametrically opposite points on the ring’s circumference first come into contact. The presented analysis deals with ring configurations past the first contact. It is shown that the configuration is stable and that for plastic materials, multiple contact points tend to develop. Collapse experiments on thin tubes are consistent with the analytical predictions.