Artificial Seismic Shadow Zone by Acoustic Metamaterials

TL;DR

This paper introduces a novel seismic protection method using acoustic metamaterials to create an artificial seismic shadow zone, effectively reducing seismic wave impact on protected structures through energy dissipation.

Contribution

It presents a new mechanical approach employing large meta-boxes with side-holes to attenuate seismic waves, differing from traditional point-based seismic protection methods.

Findings

Meta-barriers significantly reduce seismic wave amplitude.

Computer simulations confirm effectiveness of seismic shadow zones.

The method dissipates seismic energy into sound and heat.

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.