On the relationship between the microstructure of bone and its mechanical stiffness.
On the relationship between the microstructure of bone and its mechanical stiffness.
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DOI：
10.1016/0021-9290(92)90286-a
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发表时间：
1992-11
影响因子：
2.4
通讯作者：
H. Wagner;Stephen Weiner
中科院分区：
文献类型：
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作者：
H. Wagner;Stephen Weiner
最近对骨结构的研究表明，单个片层中的板状碳酸盐磷灰石晶体在片层中呈层状排列，这些层在交替的片层中取向不同。在此基础上，提出了一种新的细观力学模型，该模型考虑了材料的各向异性和几何特性。该模型结合了基本增强单元的片状几何结构、薄片和厚片的交替存在以及晶片中晶片的取向。将薄板和厚板模拟为由胶原基质内的矩形磷灰石薄片组成的正交各向异性复合层，并用经典的正交各向异性弹性理论计算薄板的杨氏模量。骨被视为这样的正交各向异性薄板弯曲成圆柱形结构的集合，并且在连续的薄板之间具有恒定的、交替的角度。细观力学模型采用修正的混合规则来解释这两种类型的薄板。该模型提供了与已发表的杨氏模量角依赖关系的实验数据类似的曲线，包括在0到90°之间的角度的局部极大值。对该模型的严格测试正在等待更多的实验数据。
A recent study of bone structure shows that the plate-shaped carbonate apatite crystals in individual lamellae are arranged in layers across the lamellae, and that the orientation of these layers are different in alternate lamellae. Based on these findings, a new micromechanical model for the Young's modulus of bone is proposed, which accounts for the anisotropy and geometrical characteristics of the material. The model incorporates the platelet-like geometry of the basic reinforcing unit, the presence of alternating thin and thick lamellae, and the orientations of the crystal platelets in the lamellae. The thin and thick lamellae are modeled as orthotropic composite layers made up of thin rectangular apatite platelets within a collagen matrix, and classical orthotropic elasticity theory is used to calculate the Young's modulus of the lamellae. Bone is viewed as an assembly of such orthotropic lamellae bent into cylindrical structures, and having a constant, alternating angle between successive lamellae. The micromechanical model employs a modified rule-of-mixtures to account for the two types of lamellae. The model provides a curve similar to the published experimental data on the angular dependence of Young's modulus, including a local maximum at an angle between 0 and 90°. A rigorous testing of the model awaits additional experimental data.