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Article Citation - WoS: 9Citation - Scopus: 10Prediction of Potential Seismic Damage Using Classification and Regression Trees: a Case Study on Earthquake Damage Databases From Turkey(Springer, 2020) Yerlikaya-Ozkurt, Fatma; Askan, AysegulSeismic damage estimation is an important key ingredient of seismic loss modeling, risk mitigation and disaster management. It is a problem involving inherent uncertainties and complexities. Thus, it is important to employ robust approaches which will handle the problem accurately. In this study, classification and regression tree approach is applied on damage data sets collected from reinforced concrete frame buildings after major previous earthquakes in Turkey. Four damage states ranging from None to Severe are used, while five structural parameters are employed as damage identifiers. For validation, results of classification analyses are compared against observed damage states. Results in terms of well-known classification performance measures indicate that when the size of the database is larger, the correct classification rates are higher. Performance measures computed for Test data set indicate similar success to that of Train data set. The approach is found to be effective in classifying randomly selected damage data.Article Citation - WoS: 5Citation - Scopus: 7Lessons Learned From Four Recent Turkish Earthquakes: Sivrice-Elazığ, Aegean Sea, and Dual Kahramanmaraş(Springer, 2024) Tunc, Goekhan; Mertol, Halit Cenan; Akis, TolgaT & uuml;rkiye is located in an earthquake-prone region where almost all of its population resides in risky areas. In the past 100 years, there has been a strong earthquake every two years and a major one every 3 years. This study investigates the impact of four recent earthquakes, that occurred between 2020 and 2023, on reinforced concrete (RC) buildings. The first, Sivrice-Elaz & imath;& gbreve;, struck the eastern part of T & uuml;rkiye on January 24, 2020, with a moment magnitude of Mw = 6.8. The second, the Aegean Sea, hit the western part of the country on October 30, 2020, with an Mw of 6.6. The third and fourth are the February 6, 2023 dual Kahramanmara & scedil; earthquakes with Mws of 7.7 and 7.6, which struck the eastern part of T & uuml;rkiye approximately 9 h apart. Immediately following these earthquakes, a technical team investigated each of the damaged areas. This study summarizes their findings on RC buildings. It was discovered that the majority of the collapsed or severely damaged RC buildings were constructed before 2000. The main reasons for this included technological limitations, specifically on producing high-quality concrete, as well as a lack of public policies and enforced laws in the construction sector to maintain an acceptable international standard. Furthermore, the damage patterns of buildings from these four earthquakes indicated poor workmanship, low material quality, improper structural framing, a common appearance of soft and weak stories, the inadequate use of shear walls, and defective reinforcement configuration. The significance of soil studies and the enforcement of building inspections are also discussed, along with the earthquake codes. The study concludes that the maximum peak ground accelerations from the dual Kahramanmara & scedil; earthquakes were almost triple the code-prescribed values. Therefore, it is recommended that the current mapped spectral acceleration values be revised and that buildings constructed before 2000 should be prioritized while determining their structural performances.Article Citation - WoS: 21Citation - Scopus: 28Damage in Reinforced-Concrete Buildings During the 2011 Van, Turkey, Earthquakes(Asce-amer Soc Civil Engineers, 2014) Baran, Eray; Mertol, Halit Cenan; Gunes, BurcuTwo major earthquakes with magnitudes Mw=7.2 (ML=6.7) and ML=5.6 occurred in eastern Turkey on October 23 and November 19, 2011. The maximum measured peak ground accelerations for the two ground motions were 0.18g and 0.25g, respectively. The earthquakes resulted in various levels of damage to RC moment-resisting frame buildings ranging from minor cracking in brick partition walls to total collapse. This paper summarizes the field observations of the Atilim University Reconnaissance Team carried out in the region a few days after the two main shocks with an emphasis on the performance of RC buildings. A summary of the evolution of the Turkish seismic design code during the last 35 years is given, followed by an explanation of the behavior of RC buildings during the October 23 and November 9 earthquakes. The deformation types that were commonly observed in the heavily damaged or collapsed RC buildings include plastic hinging in columns attributable to stiffer beams, localization of damage in ground-story columns attributable to changes in the stiffness of the lateral load-resisting system caused by brick partition walls, and shear failure of columns caused by discontinuities in the partition walls adjacent to the columns. Poor concrete quality, inadequate development and lap splice length for reinforcement, and inadequate confinement in columns also contributed to the poor seismic behavior.Review Citation - WoS: 2Citation - Scopus: 2School-based psychosocial and educational interventions for children and adolescents after the 1999 Marmara earthquakes in Turkey: A review on lessons learned(Pergamon-elsevier Science Ltd, 2024) Cihanoglu, Mine; Vatansever, Merve; Erden, GulsenThe massive earthquakes experienced in August and November 1999 affected thousands of people in the Marmara region, the most densely populated and industrialized part of Turkey. The humanitarian and economic cost was so enormous, and these earthquakes have changed the Turkish disaster management system and the Turkish people's approach to disasters. Marmara earthquakes are also considered as a milestone in the provision of psychosocial services for disaster victims. This paper aims to review the psychosocial interventions targeting children, adolescents, and their families after the 1999 earthquakes in Turkey. The progression from initial responses to more organized psychosocial interventions is outlined. Conducting the interventions at schools has ensured that thousands of children, teachers, and parents are reached in the most efficient and effective way possible. The significance of the school context in designing psychosocial interventions is highlighted and implications of the lessons learned for traumatic experiences of children and parents are also explored. It is evaluated that these inferences obtained from the Marmara earthquake in Turkey can be used in disasters around the world.
