Smart structures featuring imperfect bonding interfaces: Modeling and implications

This paper is devoted to the dynamic modeling and control of multilayered smart beams of solid cross-section with surface-bonded piezoactuator layers. In contrast to the classical assumption of the perfect bonding of constituent layers, herein the existence of interracial bonding imperfections among the layers of the host structure is stipulated. The requirements of shear traction continuity and displacement jump across each interface are used to model structures featuring imperfect bonding. Their implications on free and forced vibration control is analyzed via a combined dynamic feedback control law relating the piezoelectrically induced bending moment at the beam tip with the various kinematic response quantities. Numerical results for cantilever adaptive beams experiencing flexural motion under transient distributed loading are presented. For the case of an out-of-phase electrical activation of the smart structure, implications of the interface bonding imperfections on the structural quantities are investigated. The obtained results reveal the powerful role played by the proposed control methodology towards enhancing the dynamic response of cantilevered multilayered anisotropic beams to transient loadings. Also, the results are likely to contribute to a better understanding and reliable design of smart structures featuring interfacial bonding imperfections.