Assessment of the impact of seismic strengthening interventions on a historic masonry building: the case of Liceo Carlo Sigonio

This thesis presents a comprehensive assessment of seismic strengthening interventions applied to a historic masonry structure: the Liceo Carlo Sigonio, located in the historic centre of Modena, Italy. Following the seismic events that affected the Emilia-Romagna region in 2012, the building was declared unfit for use due to its significant structural vulnerabilities. The study begins with a detailed historical and architectural analysis of the building, highlighting its complex construction phases and structural heterogeneity. A numerical model was developed using the 3Muri software, based on the equivalent frame method, to simulate the building’s seismic response. The analysis comprised both local failure mechanisms and global non-linear static (pushover) analysis. The interventions evaluated include the installation of steel tie rods and tie beams, rigid floor diaphragms, lintels over openings, and reinforced plaster with transverse connectors. The effects of each intervention were assessed individually and in combination, comparing capacity curves, damage patterns, and safety indices before and after the retrofitting. Results demonstrate that targeted interventions significantly enhance structural performance, particularly along the weaker axis, while maintaining architectural integrity. The findings support the effectiveness of integrated strengthening strategies for the seismic rehabilitation of historic masonry buildings within the framework of Italian technical standards.