Nonlinear deformation and buckling of curvilinear pipes loaded by external pressure

The problem of loading of a thin-walled elastic pipe (a toroidal shell) by external pressure is examined in a geometrically nonlinear formulation. A numerical algorithm is used to study the nonlinear deformation of the shell and the stability of its equilibrium states when its cross section has undergone a significant change in shape. Results are presented from a determination of the critical stresses of curvilinear pipes with allowance for moments in the subcritical state. These results are compared with the approximate solution.