Harmonic waves in elastic sandwich plates

摘要: Motions of a sandwich plate with symmetric facings are studied in the framework three-dimensional equations elasticity. Both core and assumed to be isotropic linearly elastic. Harmonic wave solutions, which satisfy traction-free face conditions continuity tractions displacements at interfaces, obtained for four cases: plane strain solutions extensional motion, antisymmetric flexural SH-waves. The dispersion relation each these cases is computed. In order exhibit effect ratios facing thicknesses, elastic stiffnesses densities, on dynamic behavior plates, curves computed compared plates “thick, light, soft” as well “thin, heavy, stiff” facings. Asymptotic expressions relations extensional, flexural, SH-waves explicit form, frequencies numbers approach zero. thickness vibrations detail. resonance modal functions thickness-shear thickness-stretch motions obtained. Simple algebraic formulas predicting lowest deduced. orthogonality established.