Study of the most critical criterion method for complex structure optimization

The criteria formula used on rod and shell mixed structure based on the most critical criterion was derived using principle of virtual work. Discussions and extensions were made to the algorithm under multi load cases and multiconstraints situations according to the characteristic of aircraft structure optimization design. Verifications were carried out through an experiment on a wing structure optimization problem using the proposed method and the feasible direction method from iSIGHT software. Experimental results indicated that the proposed method could obtain results in accordance with iSIGHT, proved its correctness, while consumed less time. The proposed method had been applied to the optimization of main load carrying wing structure and the results are satisfactory. Both the experimental and practical result shows that the proposed method is an effective, fast and practical engineering optimization method.