Damping Analysis Of Sandwich Structures

The main object of the work is analysis of damping vibrations of sandwich structures in harmonic oscillations at frequencies close to natural vibrations of the structures. Three methods for calculation of sandwich constructions with damping are considered: the complex eigenvalues, the potential energy of eigenmodes and the direct calculation of frequency characteristics. Energy dissipation in the viscoelastic layers are taking into account using complex modules of elasticity theory. Nevertheless the elaborating algorithm of Lanczos method gives the opportunity to solve the motion equation of free vibrations for structures with hysteretic and viscous damping. The finite element method (FEM) is the research method applied here. Sandwich finite element models were developed for analysing sandwich beams and plates. Optimal sandwich plate design by FEM and method of informative planning is represented.