Probabilistic hazard assessment of seismically-induced slope deformations

Akbaş, Burak
Risk and safety assessment of earthquake-induced slope deformations are critical for proper management and mitigation of secondary hazards arising from the ground shaking during seismic events. Therefore, the objective of this study is threefold: i) to develop probabilistic seismic demand models (PSDMs) for seismically-induced maximum and permanent slope deformations, ii) to propose up-to-date Arias intensity (Ia) ground motion models (GMMs) for Türkiye and iii) to incorporate the proposed models into the probabilistic seismic hazard assessment (PSHA) framework. Proposed PSDMs for the crest and center of gravity of the sliding mass are correlated with static factor of safety (FSsta), spectral acceleration at 1-sec spectral period (SA_T=1s), Ia and initial fundamental period of the sliding mass (Tslope), whereas PSDMs for the toe includes SA_T=1s, Ia and Tslope. Proposed PSDMs are also tested with other existing models and case studies. Additionally, both independent and dependent Ia models are developed using the recently updated Turkish Strong Ground Motion Database which includes more than 23000 two-component recordings from 743 M>3.5 events occurred between 1983 to 2021. While the independent model utilizes piecewise magnitude, magnitude-dependent geometric attenuation, depth and site scaling terms consistent with other ground motion models, the dependent model uses SA_T=1s, to simplify the functional form. The proposed Ia models are in good agreement with both global as well as regional GMMs selected from the literature. Finally, the proposed PSDMs and GMMs are incorporated into the PSHA framework and seismically-induced slope displacement hazard curves are produced for a selected area in Türkiye.
Citation Formats
B. Akbaş, “Probabilistic hazard assessment of seismically-induced slope deformations,” Ph.D. - Doctoral Program, Middle East Technical University, 2024.