Multiobjective Design of Symmetrically Laminated Plates

Abstract

Multiobjective optimization of a symmetrically laminated composite plate is presented. Designs are obtained to realize maximum in-plane compressive load, maximum in-plane shear load, maximum bending strength, and maximum stiffness, two criteria being considered at a time. Design variables are fiber orientations and thicknesses of different layers. It is observed that nonconvex sets appear in the problem and consequently the weighting min-max method, rather than the pure weighting method, is used to reduce the vector maximum problem to a scalar one. Search for the optimum is then accomplished by a general nonlinear programming algorithm. Since exact solutions for the structural response are not available, the Rayleigh-Ritz method is employed to obtain approximate solutions. Numerical results are presented for different materials and various combinations of clamped, free and simply supported boundary conditions.