M. Reza Ahmadian - Subsea Oil & Gas Consultant, Extia Engineering Company,۰ Rue de Billancourt, ۹۲۱۰۰ Billancourt, France,۲Adjunct Professor, ESILV Engineering School, Pole Universitaire Leonard de Vinci, ۹۲۱۶ Paris, France

The objective of the present work is the development and application of a totally general approach to optimal design of composite laminates where all the required properties for the laminate are explicitly expressed as criteria of the optimization process. Our formulation is in the form of a highly non linear and non convex optimization problem subject to equality and inequality constraints. The constitutive parameters of the laminate are the active variables of the optimization problem. Constraints functions can represent any properties of the laminate, which are relevant for the design process (stiffness moduli, buckling load, strength criteria, etc.). The introduction of the polar method for plane elasticity allows us to have a function to present the different desired elastic symmetries for various combinations of design criteria; all types of elastic symmetries can also be taken into account. In order to keep the same greatest generality in solving our optimization problem, a genetic algorithm program is developed for the design of composite laminates. We show a number of numerical solutions found using our formulation and program.

Laminate, elastic symmetries, global optimization