Seismic vulnerability assessment and structural analysis of the church of Santa Maria di Piazza (Ostra Vetere, Italy)

Unreinforced masonry churches represent a significant portion of the global built heritage, yet their structural vulnerability to seismic actions remains a major concern. This study investigates the seismic performance of the Church of Santa Maria di Piazza in Ostra Vetere, Italy, through an integrated approach combining geometric surveys, material characterization, and numerical modeling. A three-dimensional finite element model (FEM) was developed to evaluate the building's response under static and dynamic loading conditions. Linear and nonlinear analyses, including modal and pushover assessments, identified critical structural weaknesses, particularly in the dome drum, nave, and vaults. The findings reveal that the church can withstand seismic events with return periods below 50 years but requires further reinforcement to improve safety and long-term preservation. The study underscores the necessity of targeted interventions to enhance resilience and ensure the conservation of historical structures in seismic-prone areas.