The last National Risk Assessment NRA for Italy was developed at the end of 2018 by the Department of Civil Protection (DPC) in response to the specific requirement of the Sendai Framework for Disaster Risk Reduction 2015–2030 to periodically adjourn the assessment of disaster risk. The methodology adopted to perform seismic risk assessment and build national seismic risk maps was specifically developed to comply with the recent Code for Civil Protection, issuing that, in addition to a solid scientific base, risk assessment should be characterized by a wide consensus of the scientific community. As a result, six research units belonging to two Centers of Competence of the DPC, namely ReLUIS (Network of university laboratories for seismic engineering) and EUCENTRE (European Centre for Training and Research in Earthquake Engineering), collaborated under the guidance and coordination of DPC to produce the recent updating of national seismic risk maps for the residential building stock. This paper describes the methodology adopted to develop the consensus-based national seismic risk assessment and presents the main results in terms of expected damage and impact measures (unusable buildings, homeless, casualties, direct economic losses).

Damage scenario and risk analyses are helpful tools for the local administrators for mitigation of potential earthquake losses at the urban-regional level. One of the main issues in developing such scenarios is the choice of proper capacity functions expressing the effective seismic supply for the existing building classes and the convolution with demand in the so-called fragility analysis. This article, as a further implementation of a recently developed mechanical based procedure for class scale quantitative risk evaluation, presents the derivation of class representative capacity curves and the relative fragility curves for slight, moderate, extensive, and complete damage states as defined by the well-known HAZUS methodology. Starting from an extensive building survey of Arenella district in Naples, southern Italy, statistics on main model input parameters are obtained for selected building classes of existing and/or pre-code RC buildings. Accordingly, a number of building models is simulated designed and analyzed in order to determine building class capacity. Fragility curves are computed simulating the fraction of “failures” within a capacity spectrum method framework. These capacity and fragility curves have been used in a companion paper by Lang et al. [2008] for the computation of damage scenarios in Arenella