VULNERABILITY OF MASONRY STRUCTURES UNDER A COMBINATION OF LOADS DUE TO TSUNAMI AND EARTHQUAKE

Tsunamis are among the most catastrophic natural events, characterized by a low probability of occurrence but severe social and economic consequences, including high casualty rates and widespread destruction. Recent events have heightened awareness within the scientific community, revealing that approximately 60% of the coastal cities in the world -including those along the Mediterranean coasts - are at risk of tsunamis. Despite historical records, research on tsunami vulnerability in the Mediterranean regions remains limited due to insufficient hazard data and poor data quality. This study investigates the vulnerability of masonry buildings typical of the Mediterranean coastline to tsunami impacts. Given that tsunamis frequently follow earthquakes, a probabilistic multi-hazard fragility assessment framework is introduced to analyze the cascading and compounding effects of earthquake-induced damage on structural performance under subsequent tsunami loading. A Monte Carlo based framework is adopted to account for uncertainties in tsunami loading and structural geometry ensuring a comprehensive vulnerability assessment. The study considers various earthquake intensities and tsunami scenarios to capture a wide range of possible multi-hazard conditions. The statistical results in terms of fragility curves demonstrate that structures become significantly more vulnerable when earthquake and tsunami hazards are considered together, as compared to assessing tsunami impact alone.