Abstract: “In this study, it is aimed to analyze the free vibration behavior of cross-ply laminated composite rectangular thick plates with mixed finite element method based on the Gâteaux differential. Mixed finite element model has eight unknowns, displacement, bending and twisting moments, rotations and shear forces. In the free vibration analysis, laminated composite rectangular thick plates are considered for different geometrical and material parameters, lamination scheme and boundary conditions. Accuracy of the presented functional and mixed finite element formulation is shown by comparing the results of numerical examples with the ones available in the literature. The results obtained in this study are found to be in good agreement”

Keywords: free vibration analysis, composite thick plates, Gâteaux differential, mixed finite element method