Bidirectional evolutionary topology optimization for structures with geometrical and material nonlinearities

In this paper, the BESO method is applied to the topology optimization for maximizing stiffness of nonlinear structures. By removing and adding elements, the performance of structures is gradually improved. The optimization process will be stopped when both the objective volume and the prescribed termination criterion are satisfied. Several examples are presented to verify the proposed optimization method. Numerical results show that the stiffness of structures optimized using combined geometrically and materially nonlinear modeling is always higher than that using linear analysis. The improvement is especially significant in cases involving buckling effects.