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A Ternary Seismic Metamaterial for Low Frequency Vibration Attenuation
Chen Chen1, Jincheng Lei1, Zishun Liu1
1International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Materials (Basel, Switzerland)
|February 15, 2022
Summary
This study introduces a new seismic metamaterial designed to block low-frequency vibrations, protecting infrastructure like buildings and bridges. The metamaterial effectively creates a band gap to attenuate harmful elastic waves.
Area of Science:
- Materials Science
- Civil Engineering
- Acoustics
Background:
- Low-frequency elastic waves pose significant threats to critical infrastructure.
- Seismic metamaterials offer a promising solution for mitigating structural vibration damage.
Purpose of the Study:
- To propose and analyze a novel ternary seismic metamaterial for low-frequency vibration attenuation.
- To investigate the band gap characteristics and vibration damping capabilities of the proposed structure.
Main Methods:
- Utilizing phononic crystal concepts to design a periodically arranged cube unit metamaterial.
- Employing finite element analysis (FEA) for vibration and band gap analysis.
- Developing and validating a simplified equivalent mass-spring model.
Main Results:
- The proposed metamaterial exhibits a low-frequency band gap of 8.5 Hz within the 0-20 Hz range.
- FEA confirms effective attenuation of low-frequency vibrations.
- The mass-spring model accurately predicts band gap ranges and aids in parameter optimization.
Conclusions:
- The developed ternary seismic metamaterial effectively blocks low-frequency elastic waves.
- The combination of FEA and the mass-spring model provides a robust framework for designing vibration-attenuating structures.
- This research offers valuable insights for enhancing the seismic resilience of infrastructure.
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