Seismic isolation. An efficient strategy for change of paradigm in earthquake resistant structural engineering

First Part

Abstract

In Argentine Republic, a large part of its territory is exposed to seismic risk. Local and regional seismological studies have shown the high seismic risk of important provinces of western Argentina, some examples are Mendoza, San Juan, Salta and Jujuy, among others. The region known as Gran Mendoza, currently has more than one million population and presents a significant seismic history. In the last 200 years there have been about 15 earthquakes that caused different levels of damage to buildings and in some cases have caused loss of human life. The best known historical antecedent is the earthquake of 1861, which caused the total destruction of the city and the death of 60% of the population. The technological advance of the last years has allowed to have new strategies to reduce and control the effect of destructive earthquakes on the constructions located in regions with seismic risk. Seismic isolation is one of those strategies. The paper presents the basic theory of seismic isolation, performs a review of the most commonly used isolation devices worldwide. In addition, a seismic isolation application for a three-level building of typical construction in a seismic zone is presented in which isolation devices different from those usually used in other seismic zones of the world were used. The paper is completed with information on the response of the building designed locally to sensitive earthquakes in the region and its comparison with an identical building, but with a fixed base. The results show the advantages of seismic isolation in relation to the constructive systems traditionally used.