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Updated: May 22, 2026
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Experimental and Data Analysis Workflow for Soft Matter Nanoindentation
Published on: January 18, 2022
Layered water in crystal interfaces as source for bone viscoelasticity: arguments from a multiscale approach
Lukas Eberhardsteiner1, Christian Hellmich, Stefan Scheiner
1a Institute for Transportation Science, Research Center for Road Engineering, Vienna University of Technology , Vienna , Austria.
Summary
Bone
Area of Science:
- Bone biomechanics
- Nanocomposite materials
- Biomaterials science
Background:
- Bone is a hierarchical nanocomposite of collagen fibrils and hydroxyapatite crystals.
- Extrafibrillar mineral, particularly crystal agglomerates, significantly influences bone's elastic properties.
- Thin water layers on crystal surfaces in agglomerates may act as weak interfaces.
Purpose of the Study:
- To investigate the role of viscous gliding at water-mediated interfaces in extrafibrillar mineral agglomerates.
- To model the viscoelastic behavior of bone at the macroscale based on nanoscale interface mechanics.
- To validate a multiscale homogenization scheme for predicting time-dependent bone phenomena.
Main Methods:
- Development of a multiscale homogenization scheme extended to viscoelasticity.
- Identification of mineral-cluster-specific creep parameters using three-point bending tests on hydrated bone.
- Validation of the model with independent experiments on partially dried bone samples.
Main Results:
- Viscous gliding at crystal interfaces contributes to bone's macroscale viscoelasticity.
- Identified creep parameters are crucial for modeling time-dependent mechanical responses.
- The model successfully predicts bone behavior across different hydration states.
Conclusions:
- Water layers at extrafibrillar mineral interfaces are key to bone viscoelasticity.
- The developed multiscale model accurately captures time-dependent mechanical properties of bone.
- This model is valuable for predicting phenomena like bone remodeling and fatigue.
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