| Abstract: | In many practical engineering applications, relatively stiff, long, circular cavities are lined with more compliant liner shells. Pressure applied through the porous walls of the confining medium can cause buckling of the shells. Such buckling is usually local in nature and occurs at a section with the biggest geometric imperfection. The paper presents experimental evidence which demonstrates that, once such a shell has been locally dented, a buckle which propagates within the confines of the cavity can be initiated. Such a buckle has the potential of completely collapsing the liner. The lowest pressure at which this buckle will propagate is established experimentally through a parametric study of the problem. The phenomenon is found to be physically similar to the propagating buckle problem which can develop in offshore pipelines. A difference is that in the case of the confined shell, the instability is shown to have a strong geometric dependence and, as a result, it can be developed in the case of thin elastic as well as elasto-plastic shells. |
