Both the distribution and orientation of anisotropic materials have great effects on the performance of civil and mechanical structures. Taking the maximum structural stiffness as the design objective, a concurrent method for determining the optimal distribution and orientation of orthotropic materials is proposed in this article. The method for determining material orientation theoretically overcomes the ‘repeated global minimum’ phenomenon, which often occurs in strain-based and stress-based methods, when the material is shear ‘strong’. Then, the concurrent optimization methodology for material distribution and orientation is developed by introducing an independent discrete topology variable and continuous material orientation angle. The optimized designs of material distribution and orientation are obtained concurrently by the gradient-based bi-directional evolutionary structural optimization method and the proposed material orientation optimization method. Numerical two- and three-dimensional examples are presented to demonstrate the effectiveness of the proposed concurrent optimization algorithm.

中文翻译：

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各向异性材料结构和取向的并发拓扑优化

各向异性材料的分布和取向对土木结构和机械结构的性能有很大影响。以最大结构刚度为设计目标，提出了一种确定正交各向异性材料最优分布和取向的并发方法。确定材料取向的方法在理论上克服了“重复全局最小值”现象，当材料剪切“强”时，这种现象在基于应变和基于应力的方法中经常发生。然后，通过引入独立的离散拓扑变量和连续的材料取向角，开发了材料分布和取向的并行优化方法。通过基于梯度的双向演化结构优化方法和提出的材料取向优化方法，同时获得了材料分布和取向的优化设计。数值二维和三维例子被提出来证明所提出的并发优化算法的有效性。