This paper demonstrates the influence of material stochasticity on buckling characteristics of higher-order shear deformable gradient plates with initial geometric imperfections. The gradient plates are assessed by smooth variation in the volume fraction of the constituents (i.e. ceramic and metal) as power-law distribution function in the thickness direction. The effective material properties are achieved by means of the Voigt model. Plate kinematic based on Reddy’s higher-order shear deformation theory (HSDT) associated with initial geometric imperfection in the transverse direction is employed. The governing differential equation is produced using a variational approach. The mean and standard deviation of the critical buckling load are evaluated using finite element method and a mean-centered first-order perturbation technique in order to highlight the variation in buckling response. Numerical results are compared both in deterministic and probabilistic frameworks along with convergence in support of efficacy and performance of the proposed model. Based on the results, it can be concluded that the combined influence of geometric imperfection and uncertain material properties prominently affect the buckling response of the gradient plates.

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This paper presents the influence of various random system parameters on dynamics response of imperfection sensitive higher order shear deformable functionally graded material (FGM) plates. Young’s moduli, Poisson’s ratio and volume fraction index are considered as random system parameters. The material properties of the FGM plates are assumed to vary along the thickness direction using simple power-law distribution in terms of the volume fraction of the constituents. The plate kinematics is based on Reddy’s higher order shear deformation theory. Finite element method (FEM) is employed in conjunction with first-order perturbation technique (FOPT) and Newmark integration scheme to explore the influence of different system parameters, like volume fraction indices, aspect ratio, material uncertainties, and imperfection amplitude on the dynamic responses of the FGM plates.

The present study explores the stochastic natural frequency of graphene reinforced functionally graded porous panels with unconventional boundary conditions. The material uncertainty is considered in the parameters associated with constituents that is, metal and graphene nanoplatelets (GPLs) individually and simultaneously. The metal matrix is reinforced with ultra-lightweight and high stiffness carbonaceous nanofiller, that is, GPLs. Halpin-Tsai micromechanics model is adopted to estimate effective Young’s modulus of the metal-GPLs composite whereas effective mass density and Poisson’s ratio are calculated using the Voigt model. The micro-structural gradation by creating pores is accomplished along the thickness direction of the panel employing certain continuous functions. These functions describe symmetric and asymmetric porosity distributions and associated patterns of GPLs. The equation of motion is developed using Euler-Lagrange’s equation which is based on C0-continuous structural kinematics with 7 degrees of freedom. Finite element modeling in conjunction with the first-order perturbation technique has been applied to quantify the stochastic natural frequency in terms of the mean and standard deviation of the natural frequency. Various results have been examined to highlight the influence of parameters especially related to porosity, and graphene nanoplatelets on the stochastic natural frequency of FG-GPLs porous panel constrained with conventional and unconventional boundary conditions.

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