INTEGRATED SEISMIC MICROZONATION FOR URBAN RESILIENCE: THE CASE OF ESKISEHIR CITY CENTER

Year 2026, Volume: 27 Issue: 1, 79 - 98, 27.03.2026

Sunay Mutlu , Yücel Güney , Muammer Tün

https://doi.org/10.18038/estubtda.1746850

https://izlik.org/JA79ZK85YA

Abstract

Enhancing urban resilience in seismically active regions is essential for reducing disaster risks and ensuring sustainable development. This study characterizes the dynamic engineering parameters of soils in Eskisehir’s city center, a region situated in Central Anatolia that faces high seismic risk due to its young alluvial deposits and proximity to active faults. To achieve this, detailed geophysical surveys were conducted using seismic refraction and microtremor (HVSR) methods at selected locations, and the resulting data were analyzed using Geographic Information Systems (GIS). The findings reveal significant spatial heterogeneity in soil behavior within the upper 30 meters. Specifically, Vs₃₀ values across the study area were found to range from 145 to 990 m/s, with low-velocity zones (145–315 m/s) heavily concentrated in densely populated districts. Consequently, the GIS-based Site Amplification (Fa) maps exhibited values ranging from 0.92 to 1.70, pinpointing specific zones with high seismic amplification potential. Furthermore, while fundamental site periods varied between 0.09–2.86 s, a critical concentration of periods in the 0.43–0.85 s range was identified. This range directly corresponds to the natural vibration periods of 4-8 story reinforced concrete buildings, indicating a high potential for destructive soil-structure resonance. These quantitative results provide an operational basis for multi-level planning processes specifically for defining priority zones in urban transformation and enforcing height restrictions in land-use decision-making thereby demonstrating the strategic role of geophysical methods in multidisciplinary disaster management.

Keywords

Urban Resilience , Seismic Microzonation , Vs30 , Site Amplification , GIS

Project Number

1105F095

INTEGRATED SEISMIC MICROZONATION FOR URBAN RESILIENCE: THE CASE OF ESKISEHIR CITY CENTER

https://izlik.org/JA79ZK85YA

Abstract

IEnhancing urban resilience in seismically active regions is essential for reducing disaster risks and ensuring sustainable development. This study characterizes the dynamic engineering parameters of soils in Eskisehir’s city center, a region situated in Central Anatolia that faces high seismic risk due to its young alluvial deposits and proximity to active faults. To achieve this, detailed geophysical surveys were conducted using seismic refraction and microtremor (HVSR) methods at selected locations, and the resulting data were analyzed using Geographic Information Systems (GIS). The findings reveal significant spatial heterogeneity in soil behavior within the upper 30 meters. Specifically, Vs₃₀ values across the study area were found to range from 145 to 990 m/s, with low-velocity zones (145–315 m/s) heavily concentrated in densely populated districts. Consequently, the GIS-based Site Amplification (Fa) maps exhibited values ranging from 0.92 to 1.70, pinpointing specific zones with high seismic amplification potential. Furthermore, while fundamental site periods varied between 0.09–2.86 s, a critical concentration of periods in the 0.43–0.85 s range was identified. This range directly corresponds to the natural vibration periods of 4-8 story reinforced concrete buildings, indicating a high potential for destructive soil-structure resonance. These quantitative results provide an operational basis for multi-level planning processes specifically for defining priority zones in urban transformation and enforcing height restrictions in land-use decision-making thereby demonstrating the strategic role of geophysical methods in multidisciplinary disaster management.

Keywords

Urban Resilience , Seismic Microzonation , Vs30 , Site Amplification , GIS

Project Number

1105F095

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