Hyperelastic continuum models for isotropic athermal fibrous networks

Area of Science:

• Biomaterials Science
• Mechanics of Materials
• Computational Biology

Background:

• Fibrous protein networks are crucial structural components in biological materials.
• Understanding their mechanical properties is vital for biomimicking materials and disease diagnostics.

Purpose of the Study:

• To develop and evaluate continuum models for isotropic, athermal fibrous networks.
• To compare the predictive capabilities of four network models (affine, three-chain, eight-chain, micro-sphere) against experimental data for collagen and fibrin networks.

Main Methods:

• Combined single-fibre models with network models to predict overall network behavior.
• Systematically investigated model performance under uniaxial tension, simple shear, and combined tension-shear loading conditions.
• Compared model predictions with experimental data for athermal collagen and fibrin networks.

Main Results:

• The affine and three-chain models accurately described both axial and shear mechanical responses.
• The eight-chain and micro-sphere models failed to capture shear response, predicting unphysical zero shear moduli at infinitesimal strains.
• Identified model limitations in predicting the mechanical behavior of fibrous networks under various loading conditions.

Conclusions:

• The affine and three-chain models are suitable for simulating athermal fibrous networks.
• This study provides guidance for selecting appropriate models for large-scale finite-element simulations of fibrous networks.
• Findings contribute to the development of biomimicking materials and diagnostic tools.