Buckling

Abstract

In the preceding chapters plastic instability and fracture have been considered as possible sources of failures. In thin-walled vessels, subjected to compressive stresses over an extensive region, the possibility of buckling must be considered also. The imposition of an external force on a vessel in equilibrium under a given basic load results in some additional deformation, which may or may not vanish upon removal of the external force. In the first case the equilibrium is stable, while it is unstable in the second. At sufficiently low values of the basic load the equilibrium will be stable, but when the basic load is increased above a critical value the equilibrium becomes unstable, any insignificant load giving rise to large, permanent deformations. Buckling is then said to occur and it may be followed by the complete collapse of the vessel.