Analyzing Structural Performance of Buildings in the Kahramanmaraş Earthquakes: the Role of Structural Systems

Abstract

The devastating earthquakes that struck Kahramanmaras on February 6, 2023 impacted 11 cities and millions of people in Turkiye, leading to immediate demolition of over 270,000 buildings due to extensive damage or collapse. The aftermath left more than 2 million people facing accommodation issues, underscoring the urgent need to enhance residential building structural performance beyond the standard "life safety performance level". This study, focusing on reinforced concrete structures, explores the correlation between structural performance and the structural systems of buildings. In the earthquake-affected region, around 90% of buildings utilize reinforced concrete (RC) structural systems. RC moment frames with or without shear walls dominate building construction in Turkey. Besides regular moment frames, wide-beam RC frames with thin slabs and one-way joists are also common. The current seismic design code allows these systems if adequate shear walls are provided, but it is observed that some recently constructed buildings violate this requirement. Both types of structural systems experienced damage during the earthquakes. A less frequent building type was shear-wall buildings, which rely solely on shear walls for lateral-load resistance. It was observed that the buildings with evenly distributed shear walls in both plan directions exhibited robust seismic performance if these wall amounts were sufficient compared to their height. Otherwise, these buildings suffered heavy structural damage. The findings of this study stress the need for a comprehensive assessment of structural systems to enhance earthquake performance and ensure the safety of lives and property in seismic regions.