Abstract
The fundamental frequencies of symmetrically laminated composite plates with irregular shapes are maximized with respect to fiber orientation angles in the layers. Based on the first-order shear deformation theory (FSDT), the eight-node quadrilateral isoparametric element is developed, and a layerwise optimization (LO) approach is extended to be combined with this finite element. In numerical examples, trapezoidal plates with different side ratios and square plates with different position of circular holes are analyzed for six different boundary conditions. Finally, the significant effects of different shapes on the maximized fundamental frequencies and the best fiber orientation are demonstrated.
