In this paper, the material length scale parameter of the modified couple stress theory for trabecular bones is studied. For this reason, experimental data for the buckling of single wet and dry trabeculae from the subchondral region of the human medial tibial plateau are used from the literature. A material length scale parameter is extracted using the modified couple stress theory-based buckling relation and the experimental results. This parameter can capture the size-dependent behavior of trabeculae and can be beneficial for micro-mechanical investigation of trabecular bones. In addition, this paper proposes a size-dependent length scale parameter for trabeculae to estimate the buckling behaviors of dry and wet trabeculae, more accurately. Therefore, this paper confirms that the softening (weakening) effects of the modified couple stress theory and size-dependent behavior of the material length scale parameter can be considered for some special cases, and additionally, a correct value for the length scale parameter of the trabecula is revealed.

中文翻译：

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松质骨中单个小梁的长度比例参数。

本文研究了改进的小梁骨耦合应力理论的材料长度尺度参数。因此，文献中使用了单个湿小梁和干小梁从人胫骨内侧软骨下区域屈曲的实验数据。利用改进的基于耦合应力理论的屈曲关系和实验结果提取了材料长度尺度参数。该参数可以捕获小梁的尺寸依赖性行为，并且对于小梁的微机械研究是有益的。此外，本文提出了一种与小梁有关的长度相关的长度尺度参数，以更准确地估计干小梁和湿小梁的屈曲行为。因此，