A technique for the multiobjective optimisation of laminated composite structures using genetic algorithms and finite element analysis

A methodology for using genetic algorithms with the finite element method to minimise a weighted sum of the mass and deflection of fibre reinforced structures with several design variables is described. The design constraint implemented is based on the Tsai–Wu failure criterion. Symmetrically laminated composite rectangular plates with eight layers are used to demonstrate the technique. Thus, the four fibre orientations and laminae thicknesses are to be determined optimally by defining a design index comprising a weighted average of the objective functions and determining the minimum. In addition, the fibre orientations and layer thicknesses must be selected from a set of discrete values. Results are presented for different load distributions, and various combinations of clamped, simply supported and free boundary conditions. The effect of aspect ratio on the results is also investigated.