Improving the overall performance of continuum structures: A topology optimization model considering stiffness, strength and stability

Abstract

Topology optimization considering material strength, structural stiffness and stability has great potential in engineering applications. In this paper, a topology optimization model considering the three vital performance indices is formulated by taking stress and buckling constrained continuum structures for compliance minimization. An effective optimization algorithm is developed for dealing with various issues and difficulties involved in the solution. The Kreisselmeier–Steinhauser (K–S) aggregation function is introduced to approximate the maximum von Mises stress together with a stability transformation method (STM) based correction scheme to reduce the approximation error. A smooth buckling aggregation function is constructed with a number of low-order buckling load factors to replace the original possibly non-smooth buckling constraints. To improve the robustness of the algorithm and achieve better designs, a continuation strategy for several optimization parameters is employed. With all these techniques, stable convergence of the iterative solution process is achieved. Three numerical examples are presented to demonstrate the effectiveness of the proposed algorithm.