Elastic and inelastic buckling of thin-walled steel liners encased in circular host pipes under external pressure and thermal effects.

Abstract This study aims to develop an analytical solution for the elastic buckling pressure and its corresponding equilibrium path of confined, thin-walled liners subjected to temperature variations. The admissible radial displacement function and the minimum potential energy of liners are employed to establish the equations of equilibrium. The steel liners are modelled with two-dimensional finite elements for both elastic and inelastic behaviors. The elastic buckling pressure and the equilibrium path from the computational model are in excellent agreement with the analytical predictions. The analytical solutions for elastic liners and the numerical results for inelastic liners with material and geometric nonlinearities compare well with their respective test results available in the literature. Parametric studies are performed in terms of temperature variation, out-of-roundness imperfection, non-uniform liner-pipe gap, pipe supporting medium flexibility, and steel liner yield strength. Highlights • Tightly confined liners buckle at reduced displacement under thermal effects. • The buckling pressure of tightly confined, perfect liners increases over 80% at 100 °C. • The buckling pressure of perfect liners with 1% gap changes little with temperature. • The softer the elastic medium, the lower the buckling pressure due to less confinement. • The buckling pressure of rigidly confined liners increases with yield strength of liners. [ABSTRACT FROM AUTHOR]