Dynamic Identification and FE Model Calibration of a Monumental Basilica

The protection of architectural heritage and monuments is an impor-tant challenge for scientific research, especially for countries exposed to natural hazards such as earthquakes. This paper presents the results of the dynamic iden-tification carried out through Ambient Vibration Tests (AVTs) and finite element (FE) model calibration of the Basilica of Santa Maria degli Angeli in Assisi (Italy), which has recently undergone restoration works due to the damages occurred dur-ing the seismic sequence that struck central Italy in 2016–2017. The complexity of the architectural heritage is emphasized by the presence of several volumes with different dynamic properties, such as the drum-dome system, the bell tower, the façade, which interact with each other through the naves and transepts. In this scenario, the identification of vibration modes involving single and/or coupled substructures becomes critical to estimate the seismic loads acting on them. To this end, an extensive experimental campaign was carried out using a dense net-work of vibration sensors deployed throughout the structure. The results of the dynamic investigations, together with other non-destructive tests carried out on the main masonry panels and columns, were used to develop and calibrate an FE model of the Basilica.