The present paper deals with the four-point bending of polyvinyl chloride beams reinforced with glass fiber clusters. The clusters, treated as orthotropic materials, were arranged periodically along the longitudinal axis of beams. The load-carrying capacity of the beams was estimated by two methods. In the first method, the beam strength was assessed using the Max-Stress, Max-Strain, Tsai–Wu, Inverse Tsai–Wu, and Hashin failure criteria. In the second one, the anisotropic Hill potential theory was employed to locally decrease the stiffness at any point of the whole structure. An analysis revealed that the Hill theory better described the true behavior of the beams at large deformations. It is also concluded that the toughness at fiber borders affects the total failure load considerably.

中文翻译：

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玻璃纤维增​​强聚合物梁的失效

本文研究了玻璃纤维簇增强聚氯乙烯梁的四点弯曲。作为正交各向异性材料处理的簇沿梁的纵轴周期性排列。梁的承载能力通过两种方法估计。在第一种方法中，使用最大应力、最大应变、Tsai-Wu、逆 Tsai-Wu 和 Hashin 破坏准则评估梁强度。在第二个中，各向异性希尔势理论被用来局部降低整个结构任何一点的刚度。分析表明，希尔理论更好地描述了梁在大变形下的真实行为。还得出结论，纤维边界处的韧性显着影响总失效载荷。