Centipede-Type Seismic Metamaterials

Previous research on seismic metamaterials has primarily focused on designing solutions to block Rayleigh waves. Seismic metamaterials targeting Lamb waves or body waves often require unit cell models as large as 10m or rely on expensive materials like steel to achieve low-frequency bandgaps. These designs are not only challenging to implement but also limited in their ability to address different types of seismic waves. To enhance the feasibility of seismic metamaterials, we replace steel with concrete and reduce the unit cell size from 10m to 2m. The key design inspiration comes from the centipede’s segmented body, which is flexibly connected by soft tissue to enable smooth movement. We utilize hollow rubber to connect concrete boxes and concrete cube cores to propose a centipede-type seismic metamaterial. The design simultaneously counters Rayleigh waves, Lamb waves, and P waves through small size and inexpensive construction materials. For Rayleigh waves, the proposed centipede-type seismic metamaterial can block waves in the 0–16.45Hz frequency range from any incident angle. The same design provides an all-directional bandgap of 5.76–9.55Hz for Lamb waves and 5.76–9.56Hz for P waves. To evaluate the attenuation performance, this study conducts transient simulations for Rayleigh, Lamb, and P waves. The results demonstrate that the attenuation frequencies observed in the transient simulations align with the band structures, verifying the effectiveness of the proposed centipede-type seismic metamaterials.