VIBRATION AND BUCKLING OF ORTHOTROPIC SKEW PLATES

Abstract

In this paper the vibration and buckling problems of orthotropic skew plates with different edge conditions are formulated in a unified manner on the basis of orthotropic plate theory using the variational method of Ritz. A double series of beam characteristic functions appropriate to the particular combination of edge conditions is employed. The free liberation problem and the buckling problem of these orthotropic skew plates are then solved individually as particular cases of the general formulation. The orthotropic properties corresponding to grooved steel plate, fibre glass-epoxy and laminated boron-epoxy cumposite are used. Frequencies and nodal patterns of vibration as well as buckling coefficients under direct and shear loadings are obtained for rhombic plates with ali edges clamped and also for plates with one pair of opposite edges clamped and Ihe other pair simply supported. Comparison with available results is made where possible. In the case of the Vibration problem, interesting features such as the crossing of frequency curves as observed in our earlier investigations on isotropic skew plates are observed in these case of orthotropic skew plates also. The symmetries of the nodal patterns and their variation with skew angle are also very interesting.