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A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials
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Mechanical performance of negative-stiffness multistable bi-material composites.
Navid Mehreganian1, Shayan Razi2, Arash S Fallah3
1Creative Design Engineering Lab (Cdel), School of Engineering, University of Liverpool, Liverpool, L69 3GH UK.
Acta Mechanica
|March 3, 2025
Summary
This study investigates negative stiffness honeycomb metamaterials (NSHM) for protective systems. Findings show bistability ratio significantly impacts NSHM performance, enabling desired negative stiffness with optimized geometry.
Area of Science:
- Materials Science
- Mechanical Engineering
- Solid Mechanics
Background:
- Metamaterials and metastructures offer superior performance under various loads.
- Multistable materials with negative stiffness are key for energy entrapment in protective systems.
Purpose of the Study:
- Investigate the mechanical performance of a negative stiffness honeycomb metamaterial (NSHM).
- Analyze quasi-static and dynamic responses under impact loading.
- Develop and validate an analytical model for NSHM energy and multistability.
Main Methods:
- Finite element method (FEM) for quasi-static and dynamic response analysis.
- Numerical simulations of localized striker and uniform plate impacts.
- Analytical modeling of total potential energy using optimization techniques.
Main Results:
- Quasi-static response is independent of the number of cells.
- Contact force peaks from striker impact are independent of constituent element count.
- High bistability ratios achieve desired negative stiffness, with optimized geometry balancing porosity and stiffness.
Conclusions:
- Bistability ratio is a critical parameter influencing NSHM performance.
- The developed analytical model accurately predicts NSHM behavior.
- Optimized NSHM designs can be achieved through geometric trade-offs for specific applications.
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