A study to characterize the mechanical properties and material constitution of adult descending thoracic aorta based on uniaxial tensile test and digital image correlation

Frontiers in Bioengineering and Biotechnology

Bioengineering and Biotechnology

Ming Pei¹  Jianhua Zhang²  Donghua Zou²  Zhengdong Li²  Jinming Wang²  Ningguo Liu² 

[1] Institute of Forensic Science, Xuzhou Public Security Bureau, Xuzhou, Jiangsu, China;Shanghai Key Laboratory of Forensic Medicine, Key Laboratory of Forensic Science, Ministry of Justice, Shanghai Forensic Service Platform, Academy of Forensic Science, Shanghai, China;

关键词: human aorta;    uniaxial tensile test;    digital image correlation;    material properties;    material constitutive model;   

DOI  :  10.3389/fbioe.2023.1178199

 received in 2023-03-02, accepted in 2023-06-05,  发布年份 2023

来源: Frontiers

【 摘 要 】

The mechanical properties and material constitution of the aorta are important in forensic science and clinical medicine. Existing studies on the material constitution of the aorta do not satisfy the practical requirements of forensic and clinical medicine, as the reported failure stress and failure strain values for human aortic materials have a high dispersion. In this study, descending thoracic aortas were obtained from 50 cadavers (dead within 24 h) free of thoracic aortic disease, aged from 27 to 86 years old, which were divided into six age groups. The descending thoracic aorta was divided into proximal and distal segments. A customized 4-mm cutter was used to punch a circumferential and an axial dog-bone-shaped specimen from each segment; the aortic ostia and calcification were avoided. Instron 8,874 and digital image correlation were used to perform a uniaxial tensile test on each sample. Four samples from each descending thoracic aorta produced ideal stress-strain curves. All parameter-fitting regressions from the selected mathematical model converged, and the best-fit parameters of each sample were obtained. The elastic modulus of collagen fiber, failure stress, and the strain showed a decreasing trend with age, while the elastic modulus of elastic fiber showed an increasing trend with age. The elastic modulus of collagen fiber, failure stress, and strain of circumferential tensile were all greater than those for axial tensile. There was no statistical difference in model parameters and physiological moduli between the proximal and distal segments. The failure stress and strain in the proximal circumferential, distal circumferential, and distal axial tensile were all greater for the male group than for the female group. Finally, the Fung-type hyperelastic constitutive equations were fitted for the different segments in different age groups.

【 授权许可】

Unknown   
Copyright © 2023 Li, Pei, Zhang, Liu, Wang and Zou.