A Strain Rate-Dependent Constitutive Model for Göttingen Minipig Cerebral Arteries
A Strain Rate-Dependent Constitutive Model for Göttingen Minipig Cerebral Arteries
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哥廷根小型猪脑动脉的应变率相关本构模型
DOI：
10.1115/1.4053796
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Monson, Kenneth
中科院分区：
文献类型：
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作者：
Pearson, Noah;Boiczyk, Gregory M.;Kote, Vivek Bhaskar;Sundaramurthy, Aravind;Subramaniam, Dhananjay Radhakrishnan;Rubio, Jose E.;Unnikrishnan, Ginu;Reifman, Jaques;Monson, Kenneth
创伤性脑损伤的计算机模拟通常用于提高对损伤-病理关系、组织损伤阈值以及头盔等防护装备的设计的理解。近几十年来，人类和动物的脑损伤模型都有了很大的发展，部分原因是包括了更详细的脑几何结构和脑血管等组织的表示。显性合并血管显著影响局部应变，并使研究人员能够研究脑损伤对血管系统的损害。虽然一些研究表明脑动脉是速率依赖的，但还没有公开发表的基于实验的、速率敏感的脑动脉本构模型。在这项工作中，我们表征了猪动脉轴向断裂的力学特性，包括准静态(0.01 S−1)和高速(>；100 S−1)，并提出了一个速率敏感模型来拟合数据。我们发现，在拉伸1.23时，准静态和高速应力-拉伸曲线变得明显不同(p <； 0.05)。此外，我们还发现，由于应变率的原因，破坏伸长率和应力都发生了显着变化。然后，应力-拉伸曲线被建模为Holzapfel-Gasser-Ogden材料，并添加了Prony级数来捕捉粘弹性的影响。最后，本文论证了在经历高应变率变形的脑动脉的材料特性中应考虑速率相关性，并为有限元实现提供了一个易于使用的模型。
Computational simulations of traumatic brain injury (TBI) are commonly used to advance understanding of the injury–pathology relationship, tissue damage thresholds, and design of protective equipment such as helmets. Both human and animal TBI models have developed substantially over recent decades, partially due to the inclusion of more detailed brain geometry and representation of tissues like cerebral blood vessels. Explicit incorporation of vessels dramatically affects local strain and enables researchers to investigate TBI-induced damage to the vasculature. While some studies have indicated that cerebral arteries are rate-dependent, no published experimentally based, rate-sensitive constitutive models of cerebral arteries exist. In this work, we characterize the mechanical properties of axially failed porcine arteries, both quasi-statically (0.01 s−1) and at high rate (>100 s−1), and propose a rate-sensitive model to fit the data. We find that the quasi-static and high-rate stress–stretch curves become significantly different (p < 0.05) above a stretch of 1.23. We additionally find a significant change in both failure stretch and stress as a result of strain rate. The stress–stretch curve is then modeled as a Holzapfel–Gasser–Ogden material, with a Prony series added to capture the effects of viscoelasticity. Ultimately, this paper demonstrates that rate dependence should be considered in the material properties of cerebral arteries undergoing high strain-rate deformations and provides a ready-to-use model for finite element implementation.