Seismic vulnerability assessment of complex masonry buildings: the case of the Garibaldi Barracks in Naples

The age of Italy’s building heritage, combined with the impact of recent major earthquakes in central Italy—which caused widespread damage and collapse—has led to increased attention on seismic vulnerability assessment and the preservation of historic structures. Monumental masonry buildings, particularly those located in historic city centers, often exhibit architectural and structural complexity due to centuries of evolution and construction in different historical periods. This complexity makes their seismic assessment particularly challenging. A common feature of these buildings is the successive addition of structural components over time, a characteristic they share with aggregate buildings—structures built in direct continuity with one another, typically sharing boundary walls. However, unlike urban aggregates, complex masonry buildings often retain a certain structural unity, which distinguishes them from more fragmented and heterogeneous aggregates. This study investigates the seismic vulnerability of the Garibaldi Barracks in Naples, a representative example of a complex masonry structure. Over the centuries, the building complex has undergone substantial transformations. The current configuration, in use for military purposes, incorporates the 14th-century Augustinian convent of San Giovanni a Carbonara, as well as two Renaissance towers that originally connected the northern and eastern defensive walls. These towers were later renovated and vertically extended. The wall segment between them was replaced by a new construction, now forming the main façade of the barracks. To evaluate the seismic response of this complex structure, nonlinear static (pushover) analyses were performed. Different models were adopted: the entire building was assessed as a whole, and separately as isolated portions, neglecting the interaction between adjacent structural bodies.