Seismic risk assessment at the territorial level is now widely recognised as essential for countries with intense seismic activity, such as Italy. Academia is called to give its contribution in order to synergically deepen the knowledge about the various components of this risk, starting from the complex evaluation of vulnerability of the built heritage. In line with this, a mechanics-based seismic fragility model for Italian residential masonry buildings was developed and presented in this paper. This model is based on the classification of the building stock in macro-typologies, defined by age of construction and number of storeys, which being information available at national level, allow simulating damage scenarios and carrying out risk analyses on a territorial scale. The model is developed on the fragility of over 500 buildings, sampled according to national representativeness criteria and analysed through the Vulnus_4.0 software. The calculated fragility functions were extended on the basis of a reference model available in the literature, which provides generic fragilities for the EMS98 vulnerability classes, thus obtaining a fragility model defined on the five EMS98 damage states. Lastly, to assess the reliability of the proposed model, this was used to simulate damage scenarios due to the 2009 L’Aquila earthquake. Overall, the comparison between model results and observed damage showed a good fit, proving the model effectiveness.

More than the 60% of the Italian residential building stock had already been built by 1974, when seismic codes were enforced on a minimal part of the country. Unreinforced masonry buildings represent most of that share, but they are typical for each region, in terms of both materials and structural configurations. The definition of ‘regional’, i.e., more specific, vulnerability and exposure models are required to improve existing forecast models. The research presents a new geographic information system (GIS)-based multilevel procedure for earthquake disaster prevention planning at urban scale; it includes multicriteria analysis, such as architectural types, structural vulnerability analysis, microzonation studies, and socio-economic aspects. The procedure has been applied to the municipality of Pordenone (PN), a district town of the Friuli–Venezia–Giulia region, in Northeast Italy. To assess the urban seismic risk, more than 5000 masonry residential buildings were investigated and common types within sub-municipal areas and exposure data were collected. Simplified mechanical analysis provided a ‘regional’ vulnerability model through typological fragility curves. The integration of results into GIS tool permitted the definition of cross-mapping among vulnerability, damage scenarios (conditional and unconditional) and exposure (seismic losses, casualties, impact), with respect to various earthquake intensities expected in the town. These results are presented at different scales: from the single building, to submunicipal area and to the entire town.

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