Earthquake isolated behavior of an existing reinforced concrete school building in Hatay under the impact of maraş earthquake

One of the most devastating earthquakes that Turkey has experienced was the Kahramanmaraş earthquake, which occurred on February 6, 2023. This earthquake, with a magnitude of 7.7 Mw, caused a high number of casualties and significant damage to buildings and infrastructure in general. Among the damaged structures, many school buildings in the region were also affected. In this study, a school building in Hatay province that suffered severe damage was selected for performance analysis. As part of the study, the structural model of the school was created and analyzed using the SAP2000 software with linear analysis methods defined in the time domain. The performance of the building was evaluated under four different conditions: the original unstrengthened model, a model with existing shear walls, a model strengthened by adding new shear walls, and shear walls + seismic isolation systems. According to TBDY-2018, when real earthquake ground motions were applied to the structure, the unretrofitted model was found to experience collapse. In contrast, the retrofitted model with added shear walls achieved the Immediate Occupancy performance level, as identified in accordance with both FEMA 356 and TBDY-2018. Similarly, the model incorporating seismic isolators was also observed to remain within the Immediate Occupancy performance level. For the different structural models, the fundamental natural period, story displacements, base shear forces, and internal forces developed in the columns were comprehensively evaluated. The use of seismic isolators reduces the loads transmitted to the structure as well as the interstory drifts, which demonstrates the necessity of employing isolation. KEY WORDS Horizontal earthquake ground motion, Seismic Isolator, earthquake, Strengthened Building, Earthquake Damage, Linear Analysis, Nonstructural Analysis, Structural Performance Analysis, Reinforced Concrete Shear Wall.