Nonlinear buckling and postbuckling behaviors of porous FG-GPLRC cylindrical shells with stiffeners subjected to external pressure

Buckling and postbuckling behaviors of porous functionally graded graphene platelets-reinforced composite (porous FG-GPLRC) cylindrical shells with stiffeners subjected to external pressures are presented in this paper. Three distribution types of porosity in the shells are considered. The smeared technique for stiffeners is employed to model the mechanical behaviors of the stiffened shells. The mechanical formulations are established by the thin shell theory considering large deflection assumption, and the Ritz method is applied for three deflection amplitudes. The postbuckling formula of the pressure-deflection and the explicit critical buckling pressures can be achieved. The numerical investigations indicate the outstanding effects of stiffeners, porosity distribution, porosity coefficient, and graphene platelet (GPL) mass fraction on the nonlinear buckling responses of the stiffened shells.