Earthquake hazard analyses and urban transformatıon plannıng: The case of Kahramanmaraş - Göksun - Karaömerli

Turkey's location on active earthquake zones necessitates consideration of earthquake hazards in urban development and investment processes. In particular, site selection studies during the construction process require a detailed evaluation of the geological, geophysical, and geotechnical characteristics of the region, as well as seismicity parameters. In this context, "Earthquake Hazard Analyses" stand out as a fundamental requirement for designing earthquake-resistant structures planned in active earthquake zones. In this study, microtremor measurements were carried out at designated points in the project area where earthquake-resistant housing is planned; dominant ground period intervals and spectral amplification ratios were determined. Based on the obtained data, the soil-structure period relationship was examined, and the earthquake hazard level of the region was determined. Furthermore, using the relationships between the building's natural period, the number of floors, and building height, the resonance zone number of floors intervals dependent on the dominant ground period were determined. Earthquake hazard levels were evaluated in detail using spectral amplification ratios. The research results show that site selection in urban transformation projects must be supported by geophysical methods to minimize the impact of earthquakes on planned new settlement areas. It has been emphasized that smart city applications based solely on ecological and technological criteria, lacking geological data, cannot provide sufficient safety against natural disasters such as earthquakes. In conclusion, if the dominant soil period is known, the number of floors and building height of the structures to be designed can be practically determined with the help of resonance zone curves. This approach offers a simplified but scientifically valid method for predicting soil-structure interaction during an earthquake. In addition, the effect of different layer thicknesses on the dominant soil period calculations was discussed, and it was concluded that using a total soil depth of 50 m is appropriate, taking into account the surface wave active depth with regulatory arrangements.