On the Compressibility of Arterial Tissue
On the Compressibility of Arterial Tissue
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DOI：
10.1007/s10439-015-1417-1
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发表时间：
2016-04-01
影响因子：
3.8
通讯作者：
McGarry, J. P.
中科院分区：
文献类型：
--
作者：
Nolan, D. R.;McGarry, J. P.
动脉组织通常被认为是不可压缩的。虽然这一假设对实验者和理论家都很方便，但动脉组织的可压缩性还没有得到严格的研究。在目前的研究中，我们提出了一种实验-计算方法来确定主动脉组织的可压缩性，我们证明了从绵羊降主动脉切除的标本是显着可压缩的。样品沿径向拉伸，以充分表征组织研磨基质的机械性能。此外，还进行了双轴测试，以充分表征增强纤维的各向异性贡献。由于实验测试的复杂性，需要非线性各向异性材料的非均匀有限变形，因此有必要实施逆有限元分析方案来表征动脉组织的力学行为。结果表明，羊主动脉组织是高度可压缩的；组织的基质成分的有效泊松比为0.44。研究还表明，材料可压缩性的正确表征对于利用双轴试验校准各向异性纤维特性具有重要意义。最后证明，正确处理材料的可压缩性对于准确预测动脉在活体类型载荷下的应力状态具有重要意义。
Arterial tissue is commonly assumed to be incompressible. While this assumption is convenient for both experimentalists and theorists, the compressibility of arterial tissue has not been rigorously investigated. In the current study we present an experimental-computational methodology to determine the compressibility of aortic tissue and we demonstrate that specimens excised from an ovine descending aorta are significantly compressible. Specimens are stretched in the radial direction in order to fully characterise the mechanical behaviour of the tissue ground matrix. Additionally biaxial testing is performed to fully characterise the anisotropic contribution of reinforcing fibres. Due to the complexity of the experimental tests, which entail non-uniform finite deformation of a non-linear anisotropic material, it is necessary to implement an inverse finite element analysis scheme to characterise the mechanical behaviour of the arterial tissue. Results reveal that ovine aortic tissue is highly compressible; an effective Poisson's ratio of 0.44 is determined for the ground matrix component of the tissue. It is also demonstrated that correct characterisation of material compressibility has important implications for the calibration of anisotropic fibre properties using biaxial tests. Finally it is demonstrated that correct treatment of material compressibility has significant implications for the accurate prediction of the stress state in an artery under in vivo type loading.