Investigating the structural damage in Hatay province after Kahramanmaraş-Türkiye earthquake sequences

On February 6, 2023, two heavy earthquakes with moment magnitudes (M_W) of 7.7 and 7.6 hit the Kahramanmaraş region in southeast Türkiye. Aftershocks of moment magnitude of 6 occurred consequently. These earthquakes affected more than 14 million people, and caused severe damage to civil infrastructure including buildings, government offices, religious buildings, dams, bridges, airports, and roads. After the earthquakes, a group of researchers visited the Hatay province to assess the response of buildings. Hatay was one of the most heavily affected cities in the region. The researchers gathered data on damaged reinforced concrete buildings, steel structures, as well as masonry buildings. This paper focuses on discussing the findings and analyzing the gathered data from reinforced concrete buildings and steel structures. A wide variety of issues that resulted in heavy damage or, in some cases, complete collapse of the buildings are discussed. These problems include construction mistakes such as insufficient shear reinforcements, neglected corrosion, utilizing low-quality concrete, insufficient development length in flexural reinforcements, and strong beam- weak column failure. In addition, various design errors including excessive torsional response of buildings, rigidity difference in two orthogonal directions of east–west and north–south of the building plan, pounding effect, short column failure, and development of weak and soft stories are described using gathered pictorial data. Finally, recommendations were made, and conclusions were drawn based on previous experimental and numerical studies of the seismic behavior of buildings as well as Turkish Building Earthquake Code (TBEC- 2018) requirements.