Effect of Seismic Isolation on Earthquake Behavior of Mid-Rise Reinforced Concrete Building Systems

When the latest updated Türkiye Earthquake Hazard Map and Active Fault Maps are examined, it is seen that a large part of Türkiye's surface area is at earthquake risk. With increasing urbanization, the majority of the population lives in cities built on active earthquake faults. The 7.8 and 7.5 magnitude earthquakes centered in Kahramanmaraş, Pazarcık, and Elbistan occurred in Türkiye on February 6, 2023, and caused significant loss of life and major damage in 10 provinces. In the damage assessment studies conducted after the earthquakes, it was determined that the damage in structures constructed with tunnel formwork systems was less than the damage in other structural systems. The importance of seismic isolators in such a severe earthquake was once again revealed. Within the scope of this study, the earthquake performance of mid-rise buildings constructed with tunnel formwork systems and mid-rise buildings constructed with reinforced concrete carcass construction systems was compared with and without isolators for different soil classes. When the obtained results were examined, it was observed that the earthquake performance of the structures constructed with the tunnel formwork system was better than that of the structures constructed with the reinforced concrete frame structure system and that in cases where a seismic isolator was used, the isolator positively affected the forces acting on the structure and the structure displacements.