On-line seismic hazard data for the new Italian building code

Abstract

The probabilistic seismic hazard of Italy was assessed in 2004 to match the requirements of the new seismic provisions. This such map, now recognized as the official reference for design according to the building and administrative issues, is the result of a comprehensive seismic hazard model that takes into account the variability in seismicity, seismogenic potential, and propagation in different areas of Italy. Since 2004, we have computed seismic hazard in terms of peak ground acceleration and spectral acceleration values for varied annual probabilities of exceedance, including a measure of their variability. These data allow as to: (1) compute site-specific seismic hazard curves and uniform hazard spectra; (2) anchor the elastic response spectra; and (3) set seismological constraints on the limit states. These seismic hazard data are stored in a database, freely accessible to all end-users via the web, where they can be downloaded or consulted through a WebGIS tool.