Multi-objective optimum of composite bolted joints by using the multi-layer convex hull method

The selection of optimum design points is difficult due to the fact that the number of Pareto optimal design points grows explosively with the increase of objective dimensions. A finer described Pareto frontier contains many more Pareto optimal design points which increase the selection difficulty. In this paper, the multi-layer convex hull method is developed to decrease the selection number of the multi-objective optimum design points. The concept multi-layer convex hull method is like onions with the convex hulls built from outside to inside. A three-objective optimum design of bolted composite joints is employed to validate this method. Result shows that the large individual number that has to be checked in the last generation is decreased significantly.