Experimental Study on a Subwavelength Auxetic Pile‐Type Metamaterial for Seismic Wave Attenuation

ABSTRACT Seismic metamaterials are an innovative passive control technology for regionally mitigating earthquake disasters. They are conceptualized from the perspective of phononic crystals, manipulating wave propagation mainly through two mechanisms—Bragg scattering and local resonance. By adopting the local resonance mechanism, this research aims to ameliorate typical pile‐type seismic metamaterials through integrating them with auxetic structures to enhance resonant behavior and obtain more suitable omnidirectional band gaps for earthquake engineering applications. The unique characteristics of auxetic structures enable the fulfillment of an ultralow frequency band gap with an impressive bandwidth, even while maintaining an excellent energy attenuation effect. It theoretically and experimentally demonstrates that the propagation of primary waves can be controlled artificially using periodic auxetic seismic metamaterial barriers. The acceleration response and energy flow are examined using one‐fifteenth scaled experiments and corresponding three‐dimensional numerical models to assess the transmission spectrum and the energy dissipation mechanism of periodic auxetic seismic metamaterial barriers. The results reveal that the attenuation zone matches the theoretical band gap very well, and the proposed seismic metamaterial exhibits clear local resonance wave modes, as evidenced by kinetic energy distribution analysis. A parametric analysis of row numbers of seismic metamaterials is also conducted to attest that periodic arrangement is essential for exerting the expected properties of band gaps. To sum up, in this study, a novel three‐dimensional seismic metamaterial, composed of an auxetic structure and concrete block, is first proposed, and its feasibility and practicality are directly validated through numerical simulations and physical experiments, making it a promising solution for designing seismic metamaterials in practice.