Modal analysis of a thick sandwich plate : A comparison between theory and experiment

Composite structures, beam, plates, and shells, are commonplace in many sectors of the automotive and aircraft industries. Use of such structures is now being considered for off-shore and naval applications because of thepotential for improved strength to weight ratio and resistance to harsh environments. This paper considers the theoretical and experimental modal analysis of a thick sandwich plate, approximately 20 feet by six feet. This plate is a scale model of a new design for a ship's deck. In service, it is the fundamental mode that is normally most problematic for a ship's deck. Results are presented from an experimental modal analysis with the plate suspended on rubber bungee cords.