3D Finite Difference Simulation for Evaluating the Possibility of Buildings as Metastructures

Date: 4/26/2019

Time: 03:45 PM

Room: Pine

The concept of metamaterials has been effectively developed for various fields of physics like electromagnetism, optics and acoustics since their advent, but their application is relatively recent in the field of seismology and earthquake engineering. Although seismic metamaterials impart an exceptional solution for seismic hazard mitigation, till now very few studies have been conducted in which the actual frequency of interest (0-10 Hz) has been the primary focus due to lack of their practical applications. In the present study we investigate whether the existing structures of a city can act as metastuctures for other structures within the city on rayleigh wave to create a band gap on earthquake engineering scale. For this purpose, several 3D simulations using visco-elastic finite difference algorithm have been performed, while varying the height and the arrangements of the structures of the city. After the analysis of the results obtained through the simulations it is concluded that structures of the city act as sub-wavelength resonators which pluck the energy from the rayleigh wave at their fundamental and higher modes of vibrations, for both longitudinal as well as their flexural modes. Finally, an ideal arrangement of structures in a city is given for which the aforementioned effect is maximum. This arrangement although ideal could act as an aid for urban planners and earthquake engineers in planning and development of new cities as well as better estimation of design parameters for earthquake resistant design of structures in the epicentral zone of a shallow damaging earthquake.

Presenting Author: Lav Joshi

Authors