Optimization of FRP composites against impact induced failure using island model parallel genetic algorithm

The present paper deals with optimization of hybrid fiber reinforced plastic (FRP) laminated plates subjected to impact loading using island model parallel genetic algorithm (IMPGA). Finite element method (FEM) and IMPGA have been used to obtain optimum laminates in terms of minimizing the cost, weight or both cost and weight of Graphite/Epoxy (T300/5208) Aramid/Epoxy (Kevlar 49) hybrid laminates. Impact induced delamination and matrix cracking have been used as failure criteria for the optimization of laminate. Fiber orientation, material and thickness in each lamina as well as number of lamina in the laminate have been used as design variables. Multi-objective approach has been used to achieve the optimum design of a laminate for combined normalized weighted cost and weight minimization. The results obtained from the integrated module show that IMPGA with FEM can lead to a global optimal solution for both single as well as multiple objective functions. It has been observed that better convergence of objective function could be obtained using IMPGA in comparison to sequential GA (SGA). Further, a significant reduction in computational time has been observed with IMPGA in comparison to SGA and the computational time decreases with increased number of processors. (c) 2005 Elsevier Ltd. All rights reserved.