free vibration of thick sandwich plate using higher order shear deformation theory and dqm for difference boundary conditions

in this paper, the effect of different boundary conditions on the free vibration analysis response of a sandwich plates is presented using higher order shear deformation theory. the face sheets are orthotropic laminated composite that follow the first order shear deformation theory (fsdt) based on rissners-mindlin (rm) kinematics field. based on energy method and hamilton's principle, the motion equations are derived considering continuity boundary conditions between layers. the frequency and mode shapes of the structure are obtained using differential quadrature method (dqm). the effects of different parameters such as face sheet to core stiffness ratio, boundary conditions and core to face sheet thickness are shown on the frequency of the sandwich plate. numerical results indicate that the frequency of the cccc and cfff sandwich plates predicted the higher and lower frequency, respectively.