Chiang, You-Rong

Hellmich, Christian

Thurner, Philipp

2024-01-10T12:54:18Z

2024-01-10T12:54:18Z

2023-09-20

<div class="csl-bib-body"> <div class="csl-entry">Chiang, Y.-R., Hellmich, C., &#38; Thurner, P. (2023, September 20). <i>A novel data-driven constitutive model for individual collagen fibrils based on hypoelasticity</i> [Conference Presentation]. X International Conference on Computational Bioenginneering (ICCB 2023), Wien, Austria.</div> </div>

http://hdl.handle.net/20.500.12708/191503

Collagens are the primary constituents at the lowest hierarchy of biological tissues (Orgel et al., 2006). Abnor-mality in the stiffness of collagen fibrils may result in severe cardiovascular diseases, such as atherosclerotic plaques (Akyildiz et al., 2017). In this context it is an open quest to describe the biomechanical properties of collagen fibrils by a constitutive model. Hyperelastic models are a powerful approach to depict the nonlinear mechanical response of biological materials (Holzapfel & Ogden, 2020). However, hyperelasticity fails to describe non-affine transformation and inherent rate-dependency observed in soft tissues (Morin et al., 2021). In this study, a data-driven hypoelastic model for individual collagen fibrils is attempted to be built within the framework of continuum theory, which represents a more general class of elastic bodies capable of in-depth discussion on fiber-rearrangement and rate-dependent elastic behavior in spatial configuration. The experimental data are provided by a previous study of atomic force microscopy (AFM) uniaxial tensile tests on individual collagen fibrils from rat tail tendons (RTT) in low strain regimes (Andriotis et al., 2018). Owing to the large aspect ratio of the collagen fibrils and the rotation-al-free tensile tests, one can infer the assumptions on linear displacement field and zero spin rate for further stress- and strain-rate calculation. Hence, the resulting hypoelasticity tensor is defined by the Cauchy stress-rate and strain-rate field, which can be derived from the force-displacement data of AFM tensile tests. With the absent knowledge on the cross-sectional area of the deformed collagen fibrils, at the current stage this research focuses on the analysis of the measured displacement, strain and force rate as well as the computation on the one-dimensional extensional stiffness. Results show that the measured displacement rates of the collagen fibrils increase with the level of displacement, and deviate from the displacement rates originally set in the experiment, being up to 1.72-fold higher. Despite the low strain, nonlinear extensional stiffness of collagen fibrils is still observed. As both the force rate and the ex-tensional stiffness reach a plateau at the strain level of approximately 2.6 from each experiment, it is suggested that the tensile response of the collagen fibrils is approaching the maximum stiffness in the first deformation regime (Svensson et al., 2013). The force-displacement profiles with respect to different set displacement rates may indicate viscoelastic behavior of collagen fibrils. Such that, the viscoelastic contribution can be supple-mented into the developing hypoelastic model with the addition of a dissipation function (Rajagopal & Srinivasa, 2011). Subsequently, this research will proceed in the estimation of the three-dimensional hypoelasticity tensor with the inclusion of microstructure.

European Commission

en

Continuum Mechanics

Biomechanics

Collagen Fibrils

A novel data-driven constitutive model for individual collagen fibrils based on hypoelasticity

Presentation

Vortrag

101034277

Conference Presentation

Technik für Biowissenschaften Doktoratsstudium

M6

C1

Biological and Bioactive Materials

Computational Materials Science

30

70

https://iccb2023.conf.tuwien.ac.at/

E317 - Institut für Leichtbau und Struktur-Biomechanik

E202 - Institut für Mechanik der Werkstoffe und Strukturen

E056 - Doctoral School

0000-0001-7588-9041

X International Conference on Computational Bioenginneering (ICCB 2023)

20-09-2023

22-09-2023

On Site

Event for scientific audience

Wien

AT

TU Wien

Chiang, You-Rong

Multi Track

Maschinenbau

Biologie

Mathematik

2030

1060

1010

30

40

30

en

conference paper not in proceedings

none

no Fulltext

Publications

http://purl.org/coar/resource_type/c_18cp

E317-02 - Forschungsbereich Biomechanik

E202 - Institut für Mechanik der Werkstoffe und Strukturen

E317 - Institut für Leichtbau und Struktur-Biomechanik

0000-0001-7588-9041

E317 - Institut für Leichtbau und Struktur-Biomechanik

E200 - Fakultät für Bau- und Umweltingenieurwesen

E300 - Fakultät für Maschinenwesen und Betriebswissenschaften

European Commission

101034277