Modeling Path Effects Due to 3D Velocity Structure for Nonergodic Ground-Motion Models: A Case Study Using Turkish Ground-Motion Data
Bulletin of the Seismological Society of America, cilt.115, sa.2, ss.602-618, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 115 Sayı: 2
- Basım Tarihi: 2025
- Doi Numarası: 10.1785/0120240055
- Dergi Adı: Bulletin of the Seismological Society of America
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), Artic & Antarctic Regions, Compendex, Computer & Applied Sciences, Geobase
- Sayfa Sayıları: ss.602-618
- Orta Doğu Teknik Üniversitesi Adresli: Evet
Özet
The objective of this study is to assess the performance of different path-effect models for developing nonergodic ground motion models (GMMs) using a Turkish ground-motion database. The cell-specific attenuation approach is widely used to capture path effects in the formulation of nonergodic GMMs. However, this approach can mainly capture ane-lastic attenuation effects associated with the spatial variation of the quality factor, and it is limited in capturing 3D velocity structure effects, which may be, in particular, relevant for long-period ground motions or short-distance and short-period ground motions. Recent efforts have introduced new models to incorporate 3D velocity structure effects; however, the assessment of these models in the context of instrumentally recorded ground motions is limited. This study assesses the performance of three path-effects models for Türkiye. Specifically, we consider the cell-specific attenuation approach and two additional models based on Gaussian processes but with a different parametrization on how they represent the spatial correlation of path effects. The results indicate that the models based on Gaussian processes outperform the cell-specific approach for long-period spectral acceler-ations and short-period ground motions at short distances, offering significant aleatory standard deviation reductions. The differences between the Gaussian process-based models are also discussed, highlighting how their parameterization is reflected in prediction patterns. This study contributes to the transition from ergodic to nonergodic approaches in performance-based earthquake engineering.