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In this research, the vibration analysis of a cylindrically curved sandwich plate rested on Winkler–Pasternak foundation is investigated. The curved sandwich plate consists of a rheological core and nanocomposite top and bottom layers which are included in polyvinylidene fluoride matrix and carbon nanotubes fiber. The core has electric properties, and it is affected by applying electric fields. At first, the governing relations for different layers are written, separately, in order to determine the constitutive equations of the cylindrically curved sandwich plate. Then, differential motion equations are derived by applying the energy method and Hamilton’s principle. With regard to achieving the set of coupled equations, an appropriate analytical approach is proposed to solve them which can be considered as SSCC and SSSS boundary conditions. Also, it is observed that increasing the volume fraction of carbon nanotubes in face sheets leads to increase in the stability of the electro-rheological sandwich plate. This finding can be employed to design building smart structures, military, aviation, marine and automotive.

In this research, semi-active control of sandwich plates with electro-rheological (ER) core and carbon nanotubes-reinforced composite facesheets using smart ER dampers is studied. Sandwich plate is subjected to the external electric field and rested on orthotropic visco-Pasternak foundation. The material properties of ER core and nanocomposite facesheets are obtained by Yalcintas model and Eshelby-Mori-Tanaka approach, respectively. The governing equations of motion are solved by a combination between finite element and Newmark methods for clamped and simply supported boundary condition. The effects of various parameters such as applied voltage, controlled electric field and initial gap of the electrodes on the vibration suppression time are discussed. The results show that the settling time of system introduced in this work is much less than previous researches in this field which is a very important advantage.