Fiber-reinforced composite (FRC) structure design by topology optimization has become a hot spot in recent years. Nevertheless, the existing researches reveal several unfavorable issues including the fiber dis-continuity, the length scale separation, the decreased design freedom, as well as the complicated fiber orientation optimization. Thus, this paper proposes a full-scale fiber-reinforced structure topology optimization method that is capable of simultaneous design for the structural topology, continuous fiber path, and its morphology (i.e., fiber volume, spacing and thickness). The method builds upon a bi-material element-wise density-based topology optimization framework, where the matrix material and fiber material are considered in a uniform finite element model without the scale separation. Furthermore, a novel fiber generation scheme is developed, in which the bi-material constraint method is introduced by combining the total solid (composite) volume constraint and local fiber proportion constraint, so as to drive the evolution of the general topology, continuous fiber path and fiber morphology, respectively. In this way, it can avoid the above existing issues of the current FRC designs. The fiber-reinforced structures can be naturally generated with continuous fiber paths. Several numerical examples for compliance minimization problems are provided to show the merits of the full-scale optimization method for fiber-reinforced structures. The interpretation design procedure and post-processing error simulation analysis are also presented to further validate the applicability of the proposed method.

通过拓扑优化的纤维增强复合材料（FRC）结构设计已成为近年来的热点。然而，现有的研究揭示了几个不利的问题，包括纤维间断，长度尺度分离，减小的设计自由度以及复杂的纤维取向优化。因此，本文提出了一种全面的纤维增强结构拓扑优化方法，该方法能够同时设计结构拓扑，连续纤维路径及其形态（即纤维体积，间距和厚度）。该方法建立在基于双材料元素的基于密度的拓扑优化框架上，在该框架中，基质材料和纤维材料在统一的有限元模型中被考虑，没有尺度分离。此外，提出了一种新的纤维生成方案，该方法将总的固体（复合）体积约束与局部纤维比例约束相结合，引入了双材料约束方法，以驱动一般拓扑，连续纤维路径和纤维的演化。形态。这样，可以避免当前FRC设计的上述现有问题。纤维增强的结构可以自然地通过连续的纤维路径生成。提供了一些用于最小化柔量问题的数值示例，以显示纤维增强结构的全面优化方法的优点。还提出了解释设计程序和后处理误差仿真分析，以进一步验证所提出方法的适用性。其中，通过结合总的固体（复合）体积约束和局部纤维比例约束引入双材料约束方法，以分别驱动一般拓扑，连续纤维路径和纤维形态的演变。这样，可以避免当前FRC设计的上述现有问题。纤维增强的结构可以自然地通过连续的纤维路径生成。提供了一些用于最小化柔量问题的数值示例，以显示纤维增强结构的全面优化方法的优点。还提出了解释设计程序和后处理误差仿真分析，以进一步验证所提出方法的适用性。其中，通过结合总的固体（复合）体积约束和局部纤维比例约束引入双材料约束方法，以分别驱动一般拓扑，连续纤维路径和纤维形态的演变。这样，可以避免当前FRC设计的上述现有问题。纤维增强的结构可以自然地通过连续的纤维路径生成。提供了一些用于最小化柔量问题的数值示例，以显示纤维增强结构的全面优化方法的优点。还提出了解释设计程序和后处理误差仿真分析，以进一步验证所提出方法的适用性。