Geometrically nonlinear buckling analysis of functionally graded carbon nanotube reinforced cylindrical panels resting on Winkler-Pasternak elastic foundation

摘要

This paper deals with geometrically nonlinear buckling analysis of functionally graded carbon nanotube reinforced (FG-CNTR) cylindrical panels. The FG-CNTR cylindrical panel is assumed to be rested on the Winkler-Pasternak elastic foundation and subjected to uniform pressure. In the FG-CNTR cylindrical panel model, uniform and three distributions of carbon nanotubes, which are graded in the thickness direction of the panel, are considered. Effective properties of materials of the panels reinforced by single-walled carbon nanotubes are estimated through a micromechanical model based on the extended rule of mixtures. Governing equilibrium equations of the FG-CNTRC cylindrical panel are obtained based on the classical shell theory and considering the von Karman geometrically nonlinearity and initial geometric imperfection. A closed form of the resulting stability equations is established via the Galekin procedure to obtain the buckling load-deflection relations in case of simply supported boundary condition. In the numerical results section, the exactness of formulation is validated by comparing the obtained results with those reported in the open database. Then, a comprehensive investigation into the influence of carbon nanotube volume fraction, carbon nanotube distribution rule, imperfection parameter, elastic foundation as well as the geometry parameters on the nonlinear buckling behaviors of the FG-CNTRC cylindrical panels is discussed in detail.