The Influence of Localised Effects on the Response and Stability of Thin-Walled Tubes
The present work is concerned with the influence of localised effects on the response and stability of cylindrical shells subject to axial forces and bending. It is now recognised that the influence of radially restrained boundary conditions on the complex and highly sensitive response of a tube under bending can substantially influence the axial stress distribution in the circular shell (Guarracino (2003)), From a numerical standpoint it has also been shown by the present authors that some boundary conditions, such as stiffening rings, which are commonly employed in submarine pipelines as buckling arrestors, can significantly influence the ultimate load that can be carried (Guarracino and Giordano (2003)).
A numerical study to analyse the influence of localised effects on the response and stability of thin-walled tubes under bending moment and axial force is presented here. The salient aspects of the problem are identified and incorporated in the model. The results obtained agree well with experimental data (Walker et al. (2003)) and confirm, once more, that collapse of the tubes can be very imperfection sensitive.