A building classification system for multi-hazard risk assessent of historical religious buildings

UnReinforced Masonry (URM) religious buildings have proven to require special attention in the context of natural hazards risk assessment due to their high vulnerability – connected to aging and types of construction — and to their strong links with communities from both an economic and historical – cultural perspective. However, the study of this building type is extraordinarily complex, especially when the analysis is conducted on a territorial scale and involves a large number of elements. In the Italian context, following the extensive damage caused by recent major earthquakes (e.g., L’Aquila 2009, Emilia 2012, and Central Italy 2016), damage detection survey forms for the post-emergency phase, both for ordinary and religious buildings, have been developed. Nevertheless, proper classification of URM religious buildings considering attributes related to vulnerability to non-seismic hazards, and worthwhile as a tool of prevention rather than damage relief, is still lacking. This paper focuses on the development of a new structural classification system for URM religious buildings based on the identification and categorization of a set of attributes related to vulnerability to landslides, earthquakes, and geological hazards (e.g., type of load-bearing wall, building height, soil type, etc.). The classification system is then validated on an initial portfolio of thirty-eight samples, located in a specific area of the Tuscany region (Italy), to classify religious buildings into distinct structural types.