Quasi-zero-stiffness seismic metamaterials for attenuating low-frequency Rayleigh waves

Abstract Abstract：In recent years, seismic metamaterials (SMs) based on the principle of local resonance have been extensively studied as a significant approach for achieving lowfrequency seismic wave attenuation. Quasi-zero-stiffness (QZS) metamaterials, characterized by high static stiffness and low dynamic stiffness, not only meet structural load-bearing requirements but also exhibit excellent low-frequency vibration isolation performance, offering a novel design concept for effective seismic wave suppression.This paper proposes a quasi-zero-stiffness seismic metamaterial (QZS-SM) for surface wave attenuation. By incorporating QZS elements, the structure can achieve ultra-low frequency broadband surface wave control in the range of 3.74-16.4 Hz. Finite element methods are employed to conduct a comparative analysis of the bandgap characteristics of different SM structures, with an in-depth exploration of vibration modes. The results indicate that, compared to cantilever beam structures, QZS components can effectively excite vertical vibrations of the resonators while suppressing horizontal and torsional vibrations, thereby significantly reducing the starting frequency of the bandgap. Furthermore, frequency domain and time domain analyses of the QZS-SMs clarify the dynamic response of the SMs and further validate the effectiveness of the study. We anticipate that this research will promote the engineering application of conventional building materials in deep sub-wavelength frequency seismic wave shielding.