Dynamic characterization of complex masonry structures: the Sanctuary of Vicoforte

Forecasting the response to dynamic and earthquake loading, for safety assessment as well as for control purposes, may benefit from vibration measurements, which are indispensable to update a mathematical model. The viability of ambient vibration testing for complex masonry structures is demonstrated here in a relevant case study of the Sanctuary of Vicoforte, near Mondovì, Italy. This monument is of great architectural significance, characterized by the largest elliptical dome in the world (axes 37.15 m × 24.80 m). Conceived in 1596 by Duke Carlo Emanuele I to serve as the mausoleum of the Savoy dynasty, the monument was affected since the earliest stages of its construction by the settlements of foundations, resulting in the opening of extensive cracks. In 1983, its dome-drum system was strengthened for fear of an imminent collapse. Since 2001 a research project has been conducted to evaluate the state of conservation and structural safety of the building. After a short description of the activities carried out to determine the structural conditions of the building, this study illustrates the salient stages of the dynamic characterization.