Investigation of RC structure damages after February 6, 2023, Kahramanmaraş earthquake in the Hatay region

Abstract From a tectonic perspective, Türkiye is a geographical region known for its high seismic activity, with some of the most active faults in the world. On February 6, 2023, two consecutive earthquakes with magnitudes of Mw 7.7 and Mw 7.6 struck Kahramanmaraş within a remarkably short time span of 9 h. This event stands out as a rare and unprecedented tectonic occurrence in terms of seismicity and tectonic activity over the past 100 years. The impact of these two major earthquakes on the region's reinforced concrete structures was significant, resulting in severe damage and the collapse of numerous buildings. It is of utmost importance to investigate and examine the design flaws and underlying factors that contributed to the damage observed in the reinforced concrete structures affected by these earthquakes. Such research will not only contribute to the improvement of structural design, seismic regulations, and quality control measures during construction but also enhance our understanding of earthquake engineering. In this study, an in-depth field investigation was conducted on reinforced concrete structures in Hatay, one of the regions most affected by the Kahramanmaraş earthquakes. The damages occurring in the buildings were documented through a detailed field survey and analyzed. A total of 540 reinforced concrete structures in the Hatay region were extensively examined, and the damages that occurred in these structures were photographed and interpreted to understand their underlying causes. Subsequently, based on the findings from the field investigation, a structural model was designed that incorporated the most significant design and construction errors responsible for the damages observed in the 540 examined structures. The devised model was subjected to static push-over analysis and nonlinear dynamic analysis using the SAP2000 finite element software, and the results obtained were interpreted.