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arXiv · 1210.5589

Artificial Seismic Shadow Zone by Acoustic Metamaterials

Sang-Hoon Kim·Mukunda P. Das
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Abstract

We developed a new method of earthquakeproof engineering to create an artificial seismic shadow zone using acoustic metamaterials. By designing huge empty boxes with a few side-holes corresponding to the resonance frequencies of seismic waves and burying them around the buildings that we want to protect, the velocity of the seismic wave becomes imaginary. The meta-barrier composed of many meta-boxes attenuates the seismic waves, which reduces the amplitude of the wave exponentially by dissipating the seismic energy. This is a mechanical method of converting the seismic energy into sound and heat. We estimated the sound level generated from a seismic wave. This method of area protection differs from the point protection of conventional seismic design, including the traditional cloaking method. The meta-barrier creates a seismic shadow zone, protecting all the buildings within the zone. The seismic shadow zone is tested by computer simulation and compared with a normal barrier.

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Sang-Hoon Kim, Mukunda P. Das. 2013-03-01. Artificial Seismic Shadow Zone by Acoustic Metamaterials. https://doi.org/10.1142/s0217984913501406

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