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A simplified approach to quasi-linear viscoelastic modeling
Ali Nekouzadeh1, Kenneth M Pryse, Elliot L Elson
1Department of Mechanical and Aerospace Engineering, Washington University, St. Louis, MO, USA. ali@biomed.wustl.edu
Journal of Biomechanics
|May 15, 2007
Summary
A new adaptive quasi-linear viscoelastic (QLV) model simplifies collagen behavior analysis. This computational approach reduces complexity in material characterization and prediction, offering improved strain history adaptation.
Area of Science:
- Biomaterials Science
- Computational Mechanics
- Rheology
Background:
- Quasi-linear viscoelastic (QLV) models are crucial for material characterization.
- Traditional QLV model fitting often involves computationally intensive numerical convolution.
Purpose of the Study:
- To introduce a novel, computationally efficient approach for treating quasi-linearity in one dimension.
- To develop and validate an adaptive QLV model for characterizing reconstituted collagen behavior.
Main Methods:
- A new principle for incorporating nonlinearity into QLV models was developed.
- The adaptive QLV model was calibrated using relaxation force data from ramp-and-hold stretching tests on collagen specimens.
- Model predictions were validated against force data during ramp loading and reloading.
Main Results:
- The new adaptive QLV model demonstrated comparable or superior prediction accuracy to existing models.
- The adaptive QLV model significantly reduced computational requirements for model calibration and response prediction.
- The model effectively captures strain history-dependent relaxation behavior.
Conclusions:
- The developed adaptive QLV model offers a more computationally efficient alternative for analyzing viscoelastic materials like collagen.
- This approach simplifies the characterization and prediction of material responses, particularly under smoothly applied deformations.
- The adaptive nature of the model allows for improved accuracy by accounting for strain history.
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