Seismic Safety Design of Sprinkler Systems.

Abstract

The recent main earthquakes in Italy (Emilia, 2012, Abruzzo, 2009) highlighted the importance of seismic design of plants in particular in the industrial sector. Indeed, in such cases, the indirect costs due to the out of services of the plants and the consequent production losses are very high and greater than the direct costs of reconstruction/reparation of the plant. For this reason, often, the insurance companies require that the principal plants (such as the sprinkler system) should be seismically designed. In case of an earthquake, the seismic design of sprinkler systems has to ensure the strength and the stability in order to avoid accidental ruptures and onerous out of services. In Italy, the seismic design of the plants became mandatory after July 2009 with the entering into force of the NTC 2008 standard. Nevertheless, foreign insurance standards, such as FM Global, are usually adopted in Italy for the seismic design of sprinklers. This practice raises the following question: “Is a sprinkler designed according to the requirements of FM standards compliant with the NTC 2008?”. This paper illustrates a comparative analysis between FM Global and the NTC 2008, highlighting the differences in terms of seismic action and strength. Finally, practical abacuses, for identifying the cases in which the FM-Global provides solutions that are in compliance with the NTC 2008 are presented.