No abstract

No abstract

Authors numerically demonstrate that the seismic surface waves from an earthquake can be attenuated by a seismic crystal structure constructed on the ground. In the study, seismic crystals with a lattice constant of kilometer are investigated in the aspect of band gaps (Stop band), and some design considerations for earthquake shielding are discussed for various crystal configurations in a theoretical manner. Authors observed in their FDTD based 2D wave simulation results that the proposed earthquake shield can provide a decreasing in magnitude of surface seismic waves. Such attenuation of seismic waves might reduce the damage in an earthquake.

No abstract

This study reports a wave-controlled sonic crystal switch device that exhibits a destructive interference-based wave to wave reverse switching effect. By applying control waves, this acoustic device, composed of a two-dimensional square lattice sonic crystal block, reduces acoustic wave transmission from input to output. The finite difference time domain simulation and experimental results confirm the wave-to-wave reverse switching effect at the peak frequencies of the second band. The proposed sonic crystal switch prototype provides a contrast rate of 86% at 11.3 kHz frequency. This wave-to-wave switching effect is useful for controlling wave propagation for smart structure applications.