At present there are approximately 5,000 structures in the world which are protected by seismic isolation (SI), energy dissipation (ED) and other modern seismic vibration passive control (SVPC) systems, such as shock transmitters (STs) and shape memory alloy devices (SMADs), and the number of such applications is increasing more and more. The conclusive influence of the features of the design rules used on the extension of application of the SVPC systems is evident. With regard to such an

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... ation, Japan has consolidated its worldwide leadership, with over 3,000 seismically isolated buildings in October 2006 and many others protected by ED systems. The Russian Federation remains second for the number of isolated buildings (550 in June 2005). Third, with 490 isolated buildings, is the P.R. China. In the USA, due to the very penalizing design code in force for SI of buildings, there are now only a few new applications of this kind (their overall number is approximately 200, although they are mostly quite important, half being retrofits). At present Italy (which is still worldwide leader as to SVPC application to bridges and viaducts) remains fifth for the number of isolated buildings already opened to activity: 43, besides 19 protected by ED or SMADs and 28 by STs. However, there is a significant increase of the number of Italian building applications of the SVPC systems completed in the last two years and of that of new projects: this occurred thanks to the new national seismic code, enforced in May 2003. As to other countries, of note are the growing use of SVPC in Taiwan and of SI of buildings in Armenia and New Zealand. Furthermore, important applications also began in Turkey, Greece, Portugal and Cyprus (many thanks to devices manufactured in Italy) and are going on in France (in particular in La Martinique island) and Chile. To be stressed are also the increasing use of SI for liquefied natural gas tanks and nuclear structures and the already significant application of the SVPC to cultural heritage, especially in Italy.