An Iterative Method of Optimal Design with Composite Laminates Containing an Elliptical Opening

Among many characteristics of modern composite materials, the superior strength of uniaxial laminates in the longitudinal direction and relative weakness in the trans verse direction is one of the main parameters to be considered in applied design. In the present study, an iterative method is developed in conjunction with the quadratic failure criterion for the design of a laminated plate containing an elliptical hole at its center. This method establishes an approximate optimal design of the laminate by choosing an excellent combination of orientation and thickness ratio for the given material. In many cases, it is shown that anisotropic laminates are much stronger than a quasi-isotropic laminate or orthotropic plate. This suggests the capability of aniso tropic materials in structural applications.