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The 2023 Kahramanmaraş earthquake sequence produced extensive liquefaction-induced ground deformations along the infilled shoreline of the port city of İskenderun, Türkiye. Observed liquefaction effects included ground settlement, seaward lateral spreading, and failures along a rubble mound seawall lining the coast. These effects, among other factors, likely contributed to ongoing flooding in İskenderun during moderate storm and high tide events following the earthquakes. The Geotechnical Extreme Events Reconnaissance (GEER) team collected detailed observations and measurements of selected sites affected by liquefaction. This paper presents lateral spreading, ground settlement, and flooding observations in İskenderun, which suggest widespread movements of the coastline relative to the current sea level. The Doğan restaurant case history is described in detail, where earthquake ground deformations and subsequent flooding damaged a dining patio, seawall, and nearby park facilities. Insights from these observations suggest a need to better understand multi-hazard liquefaction and flood consequences to enhance the resilience of coastal cities.
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Performance-based probabilistic liquefaction-induced ground settlement procedure
Performance-based procedures represent an improvement over current state-of-practice procedures that treat the assessment of seismic demand and engineering response parameters independently. Procedures used in current practice generally provide estimates of liquefaction-induced ground settlement that are inconsistent with the desired ground settlement hazard level. A recently developed probabilistic procedure to estimate liquefaction-induced ground settlement is employed to develop a new performance-based procedure that estimates ground settlement which accounts for key sources of uncertainty. The ground-motion intensity and ground settlement estimations are integrated in the proposed procedure to produce hazard curves for liquefaction-induced ground settlement. The hazard curve for ground settlement links different hazard levels with their corresponding values of ground settlement by evaluating a wide range of ground-motion intensities and site characterization parameters with their associated uncertainties. The proposed performance-based procedure also permits the evaluation of different sources of uncertainty and their effects on the ground settlement estimate.
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- Award ID(s):
- 1956248
- PAR ID:
- 10496082
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Earthquake Spectra
- Volume:
- 40
- Issue:
- 2
- ISSN:
- 8755-2930
- Format(s):
- Medium: X Size: p. 1301-1323
- Size(s):
- p. 1301-1323
- Sponsoring Org:
- National Science Foundation
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