Assessment of the damage caused by the 6 February 2023 earthquakes on old and new dated reinforced concrete buildings in Elbistan, Turkey

Abstract

On 06 February 2023, two strong earthquakes occurred in Kahramanmaraş, Türkiye. The first earthquake with a moment magnitude (Mw) of 7.7 and an epicenter in Pazarcık, was followed by a second earthquake with a moment magnitude of (Mw) 7.6 and an epicenter in Elbistan. These earthquakes have caused catastrophic life and structural loss in ten cities where more than 15 million people permanently live. Concentrating on the epicenter of the second earthquake, Elbistan, this study investigates the main characteristics of the earthquakes and the failure of the reinforced concrete buildings. Acceleration records from both earthquakes were analyzed and site surveys were conducted to evaluate the caused damages. The high number of completely collapsed buildings highlighted the vulnerability of the general old building stock constructed before 2000. Notably, unlike previous earthquakes in Türkiye, these earthquakes also affected new buildings constructed according to the recent Turkish Earthquake Code. In that respect, seismic damages seen in these buildings are presented and interpreted in this paper. To validate the observed deficiencies, a damaged building whose construction had just been completed but not yet occupied was both surveyed on site and subjected to non-linear performance analyses. The analysis results demonstrated that the damage distribution and locations in the models closely matched the observed damage after the earthquakes. In addition, the analyses also revealed the effect of brick infill walls on the building’s seismic behavior.