Seismic assessment of existing RC buildings based on different hazard maps

The current Italian structural code (NTC2008) includes the results of recent studies on Italian seismic hazard. Seismic actions are referred to a continuous scale, thus enabling a higher level of accuracy of the intensity values with respect to the past seismic classification. Such a difference can determine remarkable effects on the current seismic deficit of the existing building stock designed only to vertical loads, thus on the amount of possible retrofitting interventions. In this paper, the Italian provincial capitals and the municipalities of Basilicata region are referred to for the significant differences between design seismic actions provided by the NTC2008 code and the past seismic classification (OPCM3274) and are discussed first. Moreover, by adopting both classifications, the performances of typical RC buildings designed only to vertical loads have been assessed. Results have been compared in terms of building number and volume, as well as people residing in the Basilicata region.