Tsunami vulnerability assessment of reinforced concrete buildings on the southern coasts of Iran

This paper discusses tsunamis, one of the most destructive natural phenomena, which can cause extensive loss of life and property, particularly in coastal areas. Earthquakes, submarine landslides, volcanic eruptions, and meteorite impacts primarily trigger these events. This study investigates the vulnerability of moment resisting concrete frame buildings in the southern coastal regions of Iran along the Oman Sea, which are at risk of tsunamis generated by the Makran Fault. The primary objective of this research is to evaluate the vulnerability of moment resisting reinforced concrete frame buildings with fixed spans on the first floor—both without openings (featuring enclosing walls) and with openings (lacking enclosing walls) across varying numbers of stories (one, three, and five) under tsunami loading. For this purpose, three-dimensional modeling and analysis were conducted using Siesmostruct software. The analyses included nonlinear static pushover analysis and tsunami fragility (capacity) curves. The structures were modeled based on tsunami design codes from Japan and the United States and tsunami design guidelines. The results from pushover and capacity curves demonstrate that buildings with openings on the first floor (without enclosing walls) exhibit better resistance to tsunami inundation forces than those without openings (with enclosing walls). Additionally, taller buildings are more likely to withstand tsunami forces than shorter structures.