Stability of a Sandwich Cylindrical Shell with Core Subject to External Pressure and Pressure in the Inner Cylinder*

A generalized design model is proposed to study the stability and initial post-buckling equilibrium trajectory of sandwich cylindrical shells with elastic core that resists only transverse tension-compression. The model includes nonlinear equilibrium mixed-form equations, asymptotic equations obtained by the Koiter-Budiansky method, and the analytical solution of a homogeneous eigenvalue problem and inhomogeneous problem to find the values of the unknown functions at the critical point. The numerical results obtained indicate that the internal pressure strongly influences the critical load and initial post-buckling behavior of the shells.