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چکیده
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In this thesis, the dynamical behavior of functionally graded (FG) porous graphene platelets reinforced composite (GPLRC) truncated conical panels with elastically restrained against rotation edges under blast loading is studied based on a constrained third-order-shear deformation theory (TSDT). Different distribution types of graphene platelet (GPL) and porosity, including uniform and FG distributions, are considered. The material properties of the FG panels vary along the thickness continuously, based on the power-law distribution. Mechanical properties of the closed-cell cellular solids under Gaussian Random Field scheme are applied to characterize the variation of Poisson's ratio and the relationship between porosity coef?cients and mass density. The elastic modulus of the composite panels is obtained by employing the Halpin-Tsai micromechanics model. In real terms, the fully clamped boundary conditions are not existing. Therefore, the panels with elastically restrained against rotation edges are considered. In an air-blast, there are two phases, called positive and negative. According to literature, since this study explores the effects of intense blast loading, only the positive phase is considered. The modi?ed Friedlander equation is used for modelling the blast load. The system of motion equations in the linear elastic behavior range is derived by using Hamilton’s principle. The system of governing differential equations is discretized in the space and time-domain, respectively, using differential quadratic (DQ) and Newmark methods. For verification of the present results, a comparative fundamental frequency analysis of FG carbon nanotube-reinforced composite (FG-CNTRC) plates and panels is conducted and the dynamic transverse displacements of a laminated glass plate under different blast loading are compared with those in the existing literature. There is a good accord in all compared cases. Then, the effects of volume fraction of GPLs, thickness-to-length
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