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arXiv · 1806.05013

An inverse analysis of cohesive zone model parameter values for human fibrous cap mode I tearing

Xiaochang Leng·Lindsey Davis·Xiaomin Deng·Tarek Shazly·Michael A. Sutton·Susan M. Lessner
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Abstract

Atherosclerotic plaque failure results from various pathophysiological events, with the existence of fibrous cap mode I tearing in the arterial wall, having the potential to block the aortic lumen and correspondingly induce serious clinical conditions.The aim of this study was to quantify the interfacial strength and critical energy release rate of the fibrous tissue across the thickness. in this study, an inverse analysis method via finite element modeling and simulation approach was presented. A cohesive zone model (CZM) was applied to simulate the tearing of the fibrous cap tissue under uniaxial tensile tests along the circumferential direction. A fiber-reinforced hyperelastic model (Holzapfel-Gasser-Ogden) was implemented for characterizing the mechanical properties of bulk material. With the material parameter values of HGO model from inverse analysis process as the input for the bulk material, the interfacial strength and critical energy release rate along the tearing path or failure zones are obtained through the same method as material identification process of HGO model. Results of this study demonstrate the fibrous cap tissue tearing failure processes.

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Xiaochang Leng, Lindsey Davis, Xiaomin Deng, Tarek Shazly, Michael A. Sutton, Susan M. Lessner. 2018-06-13. An inverse analysis of cohesive zone model parameter values for human fibrous cap mode I tearing. https://arxiv.org/abs/1806.05013

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