An optimum analysis method of sandwich structures made from elastic-viscoelastic materials

Abstract

Due to a viscoelastic damping middle layer, sandwich structures have the capacity of energy consumption. In this paper, we describe the frequency-dependent property of viscoelastic materials using complex modulus model, and iterative modal strain energy method and iterative complex eigenvalue method are presented to obtain frequency and loss factor of sandwich structures. The two methods are effective and exact for the large-scale complex composite sandwich structures. Then an optimum analysis method is suggested to apply to sandwich structures. Finally, as an example, an optimum analysis of a clamped-clamped sandwich beams is conducted, theoretical closed-form solution and numerical predictions are studied comparatively, and the results agree well.

Keywords

optimum analysis / viscoelastic materials / sandwich structures / complex modulus model / loss factor

References

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