Influence of the Earthquake-Generating Mechanism of Peru, Chile, the United States, and Italy on Their Respective Seismic Isolation Standards

The use of base isolation is being implemented worldwide in seismically active countries. However, not all of these countries have an isolation standard and use a foreign one for the design of the isolation device. Using a foreign code does not reflect the seismic behavior of the country that needs to opt for that system, since a seismic standard is developed in response to the seismic generating mechanism of each country. Therefore, the objective of this research is to show the differences that exist in the seismic generating mechanism of Peru, Chile, the United States, and Italy and how these are related in their respective seismic isolation standards. The comparative analysis was carried out based on the historical seismicity of each country mentioned, the focal mechanism, and their frequency contents. It was determined that the seismic generating mechanism of Peru and Chile are similar, since they are countries that have the same seismogenic source. In addition, it is shown that the seismicity of the United States and Italy differs from the Peruvian and Chilean seismicity with respect to seismic duration and frequency content. It is also shown that the displacements of the United States earthquakes are larger than those of the other analyzed countries.