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A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials
Published on: May 18, 2015
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Proposal and validation of polyconvex strain-energy function for biological soft tissues
Takashi Funai1,2,3, Hiroyuki Kataoka4, Hideo Yokota2,5
1Industrial Research Institute of Shizuoka Prefecture, 2078 Makigaya, Aoi-ku, Shizuoka City, Shizuoka, Japan.
Bio-Medical Materials and Engineering
|March 8, 2021
Summary
A new strain-energy function ensures biological soft tissues exhibit stress that consistently increases with strain. This model accurately represents tissue behavior, improving medical equipment simulations.
Area of Science:
- Biomechanics
- Materials Science
- Computational Biology
Background:
- Mechanical simulations are crucial for developing medical equipment by assessing tissue responses.
- Accurate mechanical properties of biological tissues are essential for these simulations.
- Biological soft tissues typically show a monotonic increase in stress with strain.
Purpose of the Study:
- Propose a novel strain-energy function for biological soft tissues.
- Ensure the function guarantees a monotonically increasing stress-strain relationship.
- Validate the function's applicability to biological soft tissues.
Main Methods:
- Derived a polyconvex strain-energy function based on invariant convexity.
- Ensured the function reproduces the monotonic stress-strain trend.
- Performed curve-fitting to experimental stress-strain data for various soft tissues.
Main Results:
- Developed a function dependent solely on the first invariant.
- The function avoids unrealistic negative stresses in tension, unlike some existing models.
- Successfully fitted the function to diverse biological soft tissue data.
Conclusions:
- The derived function accurately models the monotonic stress-strain behavior of soft tissues.
- It is proposed as a suitable model for biological soft tissues.
- Uniaxial compression and equibiaxial tension can be approximated using uniaxial tension data with this function.
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