Dynamic calculation of nonlinear oscillations of viscoelastic orthotropic plate with a concentrated mass

Abstract

Plates, panels and shells made of composite material with fixed objects in the form of an additional mass have found a wide use due to their viscoelastic and strength properties. An analysis of their dynamic behavior indicates a significant effect of inhomogeneity of an associated mass type on their strength. The problem of oscillations of a viscoelastic orthotropic rectangular plate with an associated mass is considered according to the Kirchhoff-Love hypothesis in a geometrically nonlinear statement. This problem is reduced to solving the systems of nonlinear integro-differential equations with singular relaxation kernels, solved by the Bubnov-Galerkin method in combination with a numerical method based on the use of quadrature formulas. The numerical values of the approximate solution have been calculated in the Delphi programming environment. At wide range of changes in physicomechanical and geometrical parameters, the behavior of the plate has been studied. The effect of viscoelastic and inhomogeneous material properties, concentrated mass and their location on the oscillatory process of a rectangular plate is shown.

Effect of Fibers Orientation on the Nonlinear Dynamic Performance of Laminated Composite Plate under Different Loading In-plane

“…Thin-walled structures such as plates, panels and shells often play the role of a bearing surface, to which certain elements of the structure are fixed. Such elements are pads [8], wherefore, the researchers studied the effects and improvements most affected, especially in relation to composite laminated plates' geometries, such as a stiffener or a hole considered structural weaknesses and loading conditions. Instead of focusing on the plate's external dimensions, the researchers propose that damping and stiffness may be increased by reversing the direction of fibers in the layers and altering the distribution of fibers in response to load conditions [9] to their conviction that the lamination sequence on response can be used to more accurately describe the reaction at all points in a fibre-reinforced structure and examine stresses, strains, and failure [10].…”