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C. Adam:
"Moderately large flexural vibrations of composite plates with thick layers";
Talk: 14th U.S. National Congress of Theoretical and Applied Mechanics, Blacksburg, VA, USA (invited); 2002-07-23 - 2002-07-28.

Moderately large amplitude vibrations of polygonally shaped composite plates with thick layers are analyzed. Geometrical nonlinear effects arising from horizontally immovable hard hinged supports are taken into account. The effect of initial imperfections is included. Three homogeneous and isotropic layers with a common Poisson's ratio are perfectly bonded and their arbitrary thickness and material properties are symmetrically disposed about the middle plane. The Mindlin-Reissner kinematic assumptions are implemented layerwise, and as such model both the global and local response of composite plates. The continuity of the transverse shear stress across the interfaces is prescribed according to Hooke's law. The Berger's approximationof nonlinear strain-displacement relations are applied. By means of proper definition of overall cross-sectional rotations, a correspondence of this complex problem to the simpler case of a homogenized shear-deformable plate on horizontally restrained supports with effective stiffness and proper boundary conditions is found. The theory is applied to statically and dynamically loaded rectangular simply supported composite plates with various dimensions and material properties. Thereby, for the numerical solution the geometrical nonlinear terms of the differential equations of motion are treated as lateral forces acting on the linear elastic and homogenized shear-deformable plate with initial stiffness. The influence of layerwise cross-sectional rotations on the nonlinear response are discussed and results are compared with an equivalent-single-layer formulation of the problem considered. The nonlinear steady-state response of composite plates subjected to a time-harmonic lateral excitation is investigated and the phenomena of nonlinear resonance are studied.