Abstract
The carbon fiber reinforced plastics (CFRP) is classified as high performance composite materials that are superior to conventional materials in the specific strength and stiffness ratios. They are applied to light-weight structures in aircraft and space industries. In such fields, wings are often approximated as a parallelogram plate, but the past studies were carried out by using the classical plate theory. This analysis is however based on the shear deformation plate theory (FSDT). A Ritz method is used to calculate natural frequencies of symmetrically laminated parallelogram plates, and the layerwise optimization method is used to optimize the best lay-up designs. It is shown that the LO method is applicable to the parallelogram plates successfully.
