Multi-Scale Buckling and Post-Buckling Analysis of Functionally Graded Laminated Composite Plates Reinforced by Defective Graphene Sheets.

The present study focusses on buckling and post-buckling of graphene-reinforced laminated composite plates subjected to uniaxial and biaxial loadings. Poly-methyl-methacrylate (PMMA) is used for matrix. Depending on the type of graphene distribution in each layer, three patterns are considered for the plate cross-section. Graphene sheets are considered in both perfect and defective forms. Kinematics of the plate is modeled using the first shear deformation theory and for large deformation, von Karman nonlinearity is considered. Mechanical properties of each layer are evaluated using the molecular dynamics simulation. Besides, Halpin–Tsai and rule of mixtures are calibrated for graphene PMMA composite. Stability equations are solved based on the incremental-iterative type of Ritz method. In order to validate the solution procedure, comparison studies are conducted on isotropic plates. Numerical results are presented for four different types of boundary conditions. It is shown that, for all types of boundary condition, X-pattern provides higher buckling load. Furthermore, it is found that plates reinforced by defective graphene sheets with 5% vacancy provide lower buckling and post-buckling resistance with respect to those reinforced by pristine graphene. [ABSTRACT FROM AUTHOR]