Journal of Sandwich Structures and Materials, Jun 12, 2016
Free vibration of laminated composite and soft core sandwich plates resting on Winkler–Pasternak ... more Free vibration of laminated composite and soft core sandwich plates resting on Winkler–Pasternak foundations using four-variable refined plate theory are presented. The theory accounts for the hyperbolic distribution of the transverse shear strains through the plate thickness, and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. Equations of motion are derived from the dynamic version of the principle of virtual work. Navier technique is employed to obtain the closed-form solutions of antisymmetric cross-ply, angle-ply, and soft core laminates or soft core sandwich plates resting on elastic foundations. Numerical results obtained using present theory are compared with three-dimensional elasticity solutions and those computed using the first-order and the other higher-order theories. It can be concluded that the proposed theory is not only accurate, but also efficient in predicting the natural frequencies of laminated composite and soft core sandwich plates resting on Winkler–Pasternak foundations.
Abstract In this study, the vibration and deflection of a multilayered composite plate are invest... more Abstract In this study, the vibration and deflection of a multilayered composite plate are investigated based on simple and refined sinusoidal shear deformation plate theories. The plate’s core is made of a homogeneous material. Hamilton’s principle is used to derive the dynamic system of equations. The interaction between the smart composite sandwich plate and the surrounding medium is simulated by the visco-elastic foundations model. The analytical solution for the vibration problem of the simply supported plate is obtained by Navier’s approach. Influence of the magnitude of feedback control gain, magnetostrictive layer location, half-wave numbers, lamination schemes, thickness ratios, aspect ratios, core-thickness ratios, magnetostrictive-thickness ratio, and viscoelastic foundations on eigenfrequency values and deflections of the sandwich plate are discussed. Numerical results illustrate that the vibration behavior of the smart sandwich plate is dependent on the stiffness of the viscoelastic foundations, the feedback control gain value, and the magnetostrictive-thickness ratio. Also, the vibration suppression process can be improved by changing the location of the smart layers in the structure.
Mechanics of Advanced Materials and Structures, Jul 15, 2010
The bending response of sandwich plates subjected to thermo-mechanical loads is studied. The sand... more The bending response of sandwich plates subjected to thermo-mechanical loads is studied. The sandwich plate faces are assumed to have isotropic, two-constituent (metal-ceramic) material distribution through the thickness, and the modulus of elasticity, Poisson's ratio, and thermal expansion coefficient of the faces are assumed to vary according to a power law distribution in terms of the volume fractions of the
Abstract In the commented paper [Journal of Thermal Stresses 2020, vol. 43, no. 2, pp. 133–156] A... more Abstract In the commented paper [Journal of Thermal Stresses 2020, vol. 43, no. 2, pp. 133–156] Amir et al. have presented a general form of the displacement components. As it is shown in this comment, the free vibration analysis of an FG three-layered porous micro rectangular plate has been calculated using incorrect displacement field equations and reported values are inaccurate. The shape function that the displacements are based on is erroneous, and it does not properly account for the right degree.
Journal of Sandwich Structures and Materials, Jun 12, 2016
Free vibration of laminated composite and soft core sandwich plates resting on Winkler–Pasternak ... more Free vibration of laminated composite and soft core sandwich plates resting on Winkler–Pasternak foundations using four-variable refined plate theory are presented. The theory accounts for the hyperbolic distribution of the transverse shear strains through the plate thickness, and satisfies the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. Equations of motion are derived from the dynamic version of the principle of virtual work. Navier technique is employed to obtain the closed-form solutions of antisymmetric cross-ply, angle-ply, and soft core laminates or soft core sandwich plates resting on elastic foundations. Numerical results obtained using present theory are compared with three-dimensional elasticity solutions and those computed using the first-order and the other higher-order theories. It can be concluded that the proposed theory is not only accurate, but also efficient in predicting the natural frequencies of laminated composite and soft core sandwich plates resting on Winkler–Pasternak foundations.
Abstract In this study, the vibration and deflection of a multilayered composite plate are invest... more Abstract In this study, the vibration and deflection of a multilayered composite plate are investigated based on simple and refined sinusoidal shear deformation plate theories. The plate’s core is made of a homogeneous material. Hamilton’s principle is used to derive the dynamic system of equations. The interaction between the smart composite sandwich plate and the surrounding medium is simulated by the visco-elastic foundations model. The analytical solution for the vibration problem of the simply supported plate is obtained by Navier’s approach. Influence of the magnitude of feedback control gain, magnetostrictive layer location, half-wave numbers, lamination schemes, thickness ratios, aspect ratios, core-thickness ratios, magnetostrictive-thickness ratio, and viscoelastic foundations on eigenfrequency values and deflections of the sandwich plate are discussed. Numerical results illustrate that the vibration behavior of the smart sandwich plate is dependent on the stiffness of the viscoelastic foundations, the feedback control gain value, and the magnetostrictive-thickness ratio. Also, the vibration suppression process can be improved by changing the location of the smart layers in the structure.
Mechanics of Advanced Materials and Structures, Jul 15, 2010
The bending response of sandwich plates subjected to thermo-mechanical loads is studied. The sand... more The bending response of sandwich plates subjected to thermo-mechanical loads is studied. The sandwich plate faces are assumed to have isotropic, two-constituent (metal-ceramic) material distribution through the thickness, and the modulus of elasticity, Poisson's ratio, and thermal expansion coefficient of the faces are assumed to vary according to a power law distribution in terms of the volume fractions of the
Abstract In the commented paper [Journal of Thermal Stresses 2020, vol. 43, no. 2, pp. 133–156] A... more Abstract In the commented paper [Journal of Thermal Stresses 2020, vol. 43, no. 2, pp. 133–156] Amir et al. have presented a general form of the displacement components. As it is shown in this comment, the free vibration analysis of an FG three-layered porous micro rectangular plate has been calculated using incorrect displacement field equations and reported values are inaccurate. The shape function that the displacements are based on is erroneous, and it does not properly account for the right degree.
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