Seismic Isolation via I-Shaped and T-Shaped Large-Scale Phononic Metamaterials

Abstract

In this work, the attenuation of surface seismic waves from large-scale phononic metamaterials is numerically studied. The proposed metamaterials consist of rectangular trenches that form either I-shaped or T-shaped cavities embedded at the ground surface. The numerical investigation includes the study of the response of the proposed structures for different values of their geometric parameters. In addition, modifications of the proposed structures where heavy cores coated with a soft material were considered in the cavities were also numerically studied. For a more realistic numerical approach, the transmission spectrum of a selected large-scale phononic metamaterial was also investigated in a suitable half-space numerical scheme. The results of the present research showed that the studied large-scale metastructures could be a very promising potential candidate for seismic shielding applications for the protection of existing urban or countryside structures. The proposed metamaterials are low in cost and easy to construct for the protection of existing buildings, critical infrastructures, or even entire urban areas without need for any kind of intervention at them, therefore providing an effective solution in the field of seismic isolation.

Keywords

• phononic crystals
• acoustic metamaterials
• seismic metamaterials
• seismic isolation
• surface waves