Rodella Andrea
Department of Structural and Geotechnical Engineering, Sapienza University of Rome, Via Eudossiana 18, 00185 Rome, Italy.
Materials (Basel). 2025 Apr 6;18(7):1674. doi: 10.3390/ma18071674.
Fibrous materials, prevalent in biological tissues and engineered composites, undergo remodeling in response to mechanical loads, leading to plastic changes in fiber orientation. A previously developed continuum model describes this remodeling process. Building on that framework, the present study examines the extreme behaviors of such materials. Analytical results for the homogeneous response under tensile loading reveal three distinct classes: in class (A), fibers asymptotically approach a specific angle; in class (B), fibers align perpendicularly to the load direction; and in class (C), fibers align either with the load direction or perpendicularly, depending on their initial orientation. Numerical simulations are employed to analyze the non-homogeneous material response in a standard tensile test, demonstrating how differences in behavior arise from the material class and the initial fiber orientation distribution. This investigation focuses on the extreme behaviors of material classes (A) and (C), emphasizing phase segregation and transitions between auxetic and non-auxetic behavior.
纤维材料在生物组织和工程复合材料中普遍存在，会响应机械载荷进行重塑，导致纤维取向发生塑性变化。先前开发的连续介质模型描述了这种重塑过程。基于该框架，本研究考察了此类材料的极端行为。拉伸载荷下均匀响应的分析结果揭示了三种不同类型：在类型（A）中，纤维渐近地趋近于特定角度；在类型（B）中，纤维垂直于载荷方向排列；在类型（C）中，纤维根据其初始取向与载荷方向对齐或垂直排列。采用数值模拟来分析标准拉伸试验中的非均匀材料响应，展示了行为差异是如何由材料类型和初始纤维取向分布引起的。本研究聚焦于材料类型（A）和（C）的极端行为，强调相分离以及负泊松比行为和非负泊松比行为之间的转变。
