The Effect of Viscoelastic Adhesive Layers on Structural Damping of Sandwich Beams

ABSTRACT The effects of a viscoelastic adhesive layer on the dynamic response and structural damping of sandwich structures are studied by employing a newly developed sandwich beam theory. The two face layers are considered as ordinary beams (Euler beams) with both axial and bending resistance. The core material is considered to be viscoelastic. A newly developed high-order displacement field assumption is used in order to achieve a more accurate kinematics of the flexible viscoelastic core than would be possible under the classical assumptions for sandwich beams. Imperfect interface conditions between faces and core are defined as linear relations between longitudinal displacement discontinuities and the transverse shear stress at the adhesive layer. The viscoelastic properties of the adhesive layer and the core material are assumed in a complex modulus formula that is a function of frequency for a given temperature. The linear equations of motion that describe the vibration of the sandwich finite beam a...