A comparative study of anisotropic hyperelastic models of biological soft tissues

Açan, Alp Kağan
In the last two decades, there has been significant growth of interest in the mechanical behavior of biological soft tissues approached from the continuum mechanical perspective. A plenty of constitutive models have been proposed that represent the anisotropic hyperelastic behavior of biological soft tissues. Generally, invariant and fiber dispersion-based models are two main categories considered during the modeling steps. Among the anisotropic models, fiber dispersion-based constitutive models are known to have high performance for capturing the anisotropic behavior of tissues over invariant-based models. The type of the biological soft tissues and the number of available experimental data set under different loading cases play an important role in choosing the appropriate model. With the increasing number of hyperelastic models, a comparison among the models and choosing a proper one becomes a crucial factor for researchers in the field. In this study, the fitting performance of 9 anisotropic hyperelastic models has been investigated for three different tissues, abdominal aortic aneurysm tissue, linea alba, and rectus sheath. In order to obtain the parameters of each constitutive model, a genetic algorithm has been utilized. Further improvement of the results is achieved through the fmincon utility of MATLAB. Equibiaxial dataset for abdominal aortic aneurysm tissue, uniaxial dataset for linea alba, and uniaxial tension dataset for rectus sheath have been considered during parameter optimization.


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Citation Formats
A. K. Açan, “A comparative study of anisotropic hyperelastic models of biological soft tissues,” M.S. - Master of Science, Middle East Technical University, 2021.