Vibration and stability of an initially stressed thick plate according to a high-order deformation theory

In this paper, the average stress method is used to derive the governing equation for a thick rectangular plate according to a high-order deformation theory. The applied load is taken to be a combination of a pure bending stress plus an extensional stress in the plane of the plate. The buckling loads and natural frequencies of simply supported plates are also investigated. Present results based on high-order theory are compared with the results of Brunelle's theory and Reddy's theory. In addition, the effects of various parameters on the natural frequencies are studied. More accurate results can be obtained by using the present theory than those of the other theories.