Study on vibration damping performance of a petal-shaped seismic metamaterial

Seismic metamaterial (SM) is a new vibration damping technology, but the bandgap is difficult to concentrate in the low frequency range due to the limitation of the lattice size and there is a lack of experiments for validation. Based on this, we propose a petal-shaped seismic metamaterial by numerical simulation combined with experiments to change the internal scatterer into a petal-shaped consisting of four sectors. This structure can form an ultra-low frequency bandgap to cover the frequency band where the seismic energy is concentrated and provide effective attenuation of seismic waves. Firstly, the energy band structure and vibration modes are calculated by numerical simulation. The effects of geometric and material factors on the bandgap are analyzed with the vibration modes. Then the frequency response curves of lamb waves on SM are calculated. And the scaled-down model is fabricated and vibration tests are conducted. The results show that the new two-dimensional SM has excellent vibration damping performance compared with conventional structures and can generate low-frequency bandgap. It has potential applications in the field of seismic isolation and attenuation of buildings.