THE APPLICATION OF GEP IN TRUSS STRUCTURE OPTIMIZATION
The paper described the basic principle of Gene Expression Programming(GEP) algorithm and its realization process in parameter optimization,and then applied GEP to the truss structural optimization design.For the standard algorithm tends to be trapped in local optima and has the shortcoming of slow convergence,the backtracking mechanism was introduced,that is,to use the elite individual of the generation before stagnation to replace all worst individuals of the stagnation generation,in such a way to make the better individuals have more opportunities to evolve in different directions,thus the search space of optimal solution is expanded.The results of the 25-bar space truss sizing optimization show that the search efficiency is improved greatly,and the 72-bar space truss example proves that the method in the structural optimization is feasible and effective.