Seismic vulnerability assessment of Italian masonry churches at territorial scale

Masonry churches represent one of the most important assets of Italian cultural heritage. Earthquakes that struck Italy in the last years evidenced severe states of damage and, in the worst cases, significant structural collapses, stressing the seismic vulnerability of this construction typology and the need to define reliable preventive strategies to protect them from the effects of future earthquakes. This paper provides a synthesis of a large research activity aimed at checking and integrating the existing methodology currently adopted by the Italian Guidelines (DPCM 2011) for the seismic risk assessment of cultural heritage. The proposed procedure has been calibrated in the light of the damage scenario observed in the aftermath of the 2009 L'Aquila earthquake and then applied to 64 three-nave churches. The methodology could be also employed to predict damage level distribution due to different earthquake intensity levels. Finally, a first attempt to define useful strategies for defining effective retrofitting strategies is provided.