Influence of invariant material parameters on the flexural optimal design of thin anisotropic laminates

A general discussion of the optimal solutions to the problems of maximum stiffness, buckling load and modal frequencies for rectangular laminates is proposed. The study is based upon some invariant dimensionless material parameters. The conditions giving rise to the same objective function for the three cases are discussed and a new physical meaning of the objective as a stiffness modulus is proposed. The geometrical and material conditions giving rise to non-trivial optimal solutions are also discussed.