Robust topology optimization design of a multi-material structure considering load uncertainty

The traditional topology optimization design is generally based on single-material and deterministic conditions, it is difficult to consider the robustness of structural performance. Here, aiming at the load uncertainty in practical engineering, the robust topology optimization design methodwas studied. The multi-material interpolation model was characterized based on the ordered-solid isotropic microstructures with penalization (Ordered-SIMP). The weighted objective function forthe mean and standard deviation of structural flexibility under the load probability distribution was constructedand assisted by volume constraints. When load satisfied the random field distribution, the load random field was transformed into a weighted sum of finite uncorrelated load random variables using Karhunen-Loèveexpansion, and the sparse grid numerical integration method was employed to convert the robust topology optimization of multi-material structure into solving a set of multi-condition weighted multi-objective deterministic topology optimization design problems. The effectiveness of the proposed method and the robustness of optimization resultswere verified with numerical examples. The results demonstrated that good topological configurationscan be effectively achieved for combination schemes of different materials; compared with deterministic designs, robust designs can have different material layout schemes and more stable structural performance. © 2019, Editorial Office of Journal of Vibration and Shock. All right reserved.