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Flat lens effect on seismic waves propagation in the subsoil.

ABSTRACT: We show that seismic energy simulated by an artificial source that mainly propagates Rayleigh surface waves, is focused in structured soil made of a grid of holes distributed in the ground. We carry out large-scale field tests with a structured soil made of a grid consisting of cylindrical and vertical holes in the ground and a low frequency artificial source (<10?Hz). This allows the identification of a distribution of energy inside the grid, which can be interpreted as the consequence of a dynamic anisotropy akin to an effective negative refraction index. Such a flat lens reminiscent of what Veselago and Pendry envisioned for light opens avenues in seismic metamaterials to counteract partially or totally the most devastating components of seismic signals.

SUBMITTER: Brule S

PROVIDER: S-EPMC5741748 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Flat lens effect on seismic waves propagation in the subsoil.

Brûlé Stéphane S Javelaud Emmanuel H EH Enoch Stefan S Guenneau Sébastien S

Scientific reports 20171222 1

We show that seismic energy simulated by an artificial source that mainly propagates Rayleigh surface waves, is focused in structured soil made of a grid of holes distributed in the ground. We carry out large-scale field tests with a structured soil made of a grid consisting of cylindrical and vertical holes in the ground and a low frequency artificial source (<10 Hz). This allows the identification of a distribution of energy inside the grid, which can be interpreted as the consequence of a dyn ...[more]

PMID: 29273798

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