Confinement of historic brickwork columns with steel strands: a case study

Structural reinforcement of historic masonry buildings is crucial for preserving their historical, cultural, and architectural significance. These often centuries-old structures face seismic vulnerabilities and gradual deterioration over time. Implementing retrofitting measures is essential to improve their earthquake resilience, ensuring public safety and minimizing the risk of casualties during seismic events. Advances in material technology are transforming masonry reinforcement, enhancing the strength and durability of structures while maintaining their historic integrity. This paper presents a novel application through a case study in Italy. The Monastery of St Girolamo, a porticoed religious structure dating to the fourteenth century, has suffered extensive cracking in several of its octagonal brickwork columns over the course of centuries. Stainless steel strand, a material known for its high strength and corrosion resistance, is used as reinforcement by confining the mortar bed joint in which the strand is applied as a tensioned wrapping. Their use in masonry retrofitting ensures long-term structural stability, reduces maintenance demands, and improves the safety and longevity of the building. In this case study, a preventive unloading of the brickwork column was required and was achieved by lifting the vault with hydraulic jacks. The case study demonstrated the effectiveness of this innovative reinforcement technique in significantly enhancing the vertical load-bearing capacity of historic brickwork columns.