  A zero-frequency seismic metamaterial (ZFSM) consisting of a three-component
seismic metamaterial plate and a half space is proposed to attenuate ultra-low
frequency seismic surface waves. The design concept and models are verified
firstly by lab-scale experiments on the seismic metamaterial consisting of a
two-component seismic metamaterial plate and a half space. Then we calculate
the band structures of the one-dimensional and two-dimensional ZFSMs, and
evaluate their attenuation ability to Rayleigh waves. A wide band gap and a
zero-frequency band gap (ZFBG) can be found as the band structure of the
seismic metamaterial is almost equal to the band structure of the seismic
metamaterial plate plus the sound cone. It is found that the Rayleigh waves in
the ZFSM are deflected and converted into bulk waves. When the number of the
unit cells of the ZFSM is sufficient, the transmission distance and deflection
angle of the Rayleigh waves in the ZFSM are constant at the same frequency.
This discovery is expected to open up the possibility of seismic protection for
large nuclear power plants, ancient buildings and metropolitan areas.

Applied Physics