Buckling and vibration of rectangular laminates with cut off regions

The pure global buckling and vibration of four sides simply-supported as well as clamped orthotropic rectangular laminates having multiple rectangular cut off regions that are symmetric with respect to mid-plane have been studied by treating the remaining cut off regions as uniform plates with reduced stiffnesses. The variation of stiffness of the plate is represented by Fourier series. Some numerical results for the pure global buckling bad prediction due to its reduced flexural stiffness for typical cases of rectangular middle-plane symmetric cut off regions are presented.