Restoration Study of a Masonry Monumental Building in Thrapsano, Greece

This study investigates structural integrity and proposes retrofitting solutions for the historical two-storey school building in Thrapsano, Crete, severely impacted by the September 2021 earthquake. An extensive methodology was adopted, incorporating field surveys, material characterization, finite element modeling, and experimental analysis. The assessment is focused on identifying structural damage, such as cracking and delamination in masonry walls, and evaluating the dynamic and static performance of the load-bearing system under seismic loads. Key interventions include grouting for masonry reinforcement, replacement of mortar with compatible materials, stitching of cracks, and the addition of reinforced concrete and metallic tie elements to enhance diaphragm action. Advanced numerical simulations, validated through experimental data, were employed to model the pre- and post-retrofit behavior of the structure. The proposed retrofitting measures align with Eurocodes 6 and 8, and the Greek code for masonry structures (KADET), aiming to restore the structural stability and improve seismic resilience while respecting the building’s historical significance. The results from the finite element analysis confirm the effectiveness of the interventions in reducing tensile stresses and improving load redistribution, ensuring compliance with modern safety standards. This case study offers a framework for the seismic retrofitting of heritage structures in a similar context.