Vulnerability analysis on a dataset of long-span timber structures in Italy

Long-span structures, such as school gyms and sports centres, are often used by the Italian Department of Civil Protection (DPC) as post-catastrophe shelters or headquarters. The Emilia 2012 earthquake drew the attention of the DPC to this type of structure due to the damage that many of these buildings suffered. In this paper, a dataset of 101 timber structures was analysed based on a simplified methodology that detects the major vulnerabilities in long-span timber roofs to help planning further investigations and retrofit interventions. The methodology analyses the elements most vulnerable to the seismic action quantitatively and qualitatively, with fast and straightforward approaches. The quantitative evaluation of the vulnerabilities was achieved by applying the Italian Building Code. The aspects not considered in the quantitative evaluation were instead assessed through qualitative parameters inspired by damage identification forms, such as the AeDES form. The structures analysed are located near the epicentres of the last strong earthquakes that struck Italian territory: Abruzzo 2009, Emilia 2012, and central Italy 2016. Damage and retrofits, identified by interviewing owners, designers, and builders, showed a good correlation between the real behaviour shown by the surveyed structures and the vulnerabilities detected by the simplified methodology.