Paraskevi Modé, Marcos Julien Alexopoulos, Raouf Sobhani, Constantine C. Spyrakos, Denis Istrati
Cultural heritage (CH) sites along the Mediterranean coast are exposed to tsunami hazards that remain insufficiently quantified in current risk assessment frameworks. This study presents a probabilistic tsunami risk assessment methodology for coastal cultural heritage, integrating offshore tsunami hazard predictions, GIS-based inundation modelling, analytical tsunami load formulations, and advanced structural damage models. Offshore tsunami hazard and coastal inundation are evaluated for the archaeological site of Kolona at Aegina in Greece, for five Average Return Periods (ARPs), allowing spatially explicit estimation of flow depth and hydrodynamic demand at the site scale. Tsunami-induced loads are derived following established analytical approaches, with special consideration given to the vulnerability of heritage elements and the absence of comprehensive tsunami guidelines specifically for CH typologies. Structural response is simulated using detailed material and three-dimensional finite elements to estimate stresses, strains, and displacements in key components. The results indicated that drag-related forces primarily govern the structural response, especially under higher return-period events. The distributions of stress, strain, and displacement at the direction of the tsunami showed pronounced spatial variability, influenced by local geometry, construction characteristics, and flow exposure. The results also include inundation maps for both the surrounding coastal area and the Kolona site, sensitivity analysis with respect to spatial resolution, and cumulative damage indicators across all five considered ARPs. Damage maps are further developed to identify spatial patterns of risk across the entire site. The proposed framework provides a robust basis for prioritising conservation efforts, informing mitigation strategies, and supporting long-term tsunami adaptation planning in the Mediterranean region.