Two petrochemical facilities, located in the Dortyol district of Hatay metropolitan city along the Mediterranean coastline in Turkiye were shaken by the February 6, 2023, M7.8 Pazarcik and M7.6 ...Ekinözü-Elbistan earthquakes in Kahramanmaraş. This study investigates their seismic performances from a seismic soil liquefaction engineering perspective, addressing several key aspects: the i) identification of surface manifestations of seismic soil liquefaction, including soil ejecta, ground deformations, and displacements, ii) examination of subsurface soil characteristics, iii) evaluations of soil liquefaction susceptibility and triggering, iv) analyses of post-liquefaction ground settlements, lateral deformations, and displacements, and v) comparisons of these observed outcomes with predicted results. The assessment results indicated that liquefaction triggering evaluations, based on the SPT- and CPT-based semi-empirical methods of Cetin et al. (2018) and Moss et al. (2006), respectively, were consistent with observed field manifestations of liquefaction or their absence. However, estimated settlements obtained from the liquefaction-induced volumetric settlement procedures of Tokimatsu and Seed (1984), Shamoto et al. (1998) and Cetin et al. (2009), underestimated field settlements. This underestimation was partially explained by the additional contribution of lateral spreading deformations to field settlements, which were not considered due to one-dimensional nature of these volumetric settlement assessments. Additionally, semi-empirical correlations of Hamada et al. (1986) and Youd et al. (2002) consistently overestimated observed lateral displacements. The discrepancies in settlement and lateral spreading displacements are believed to stem from the presence of liquefaction susceptible fine-grained and/or gravelly units, which may have higher residual shear strengths and/or produce higher volumetric strains than typical clean sand layers in case history sites used for developing these semi-empirical methods. The documented field performances and assessment results are hoped to contribute to further developing and refining/calibrating increasingly accurate and reliable empirical and/or analytical methods for assessing hazards related to liquefaction triggering, and liquefaction-induced ground deformations and displacements.
•Liquefaction manifestations observed in two Petrochemical Facilities (Facility-A and Facility-M) in Hatay.•Lateral displacements and settlements mapped as 58 cm and 40 cm, respectively.•Volumetric settlements predicted by Tokimatsu and Seed (1984)Shamoto et al. (1998) and Cetin et al. (2009).•Lateral displacements predicted by Hamada et al. (1986) and Youd et al. (2002).
The performance of a Metallurgical Facility located on the Dörtyol-Hatay coast is investigated from seismic soil liquefaction engineering perspective. The facility was shaken by the M7.8, and M7.6 ...Pazarcık and Ekinözü-Elbistan Kahramanmaraş earthquake sequence. This paper presents the assessment results of soil liquefaction triggering and induced ground deformations at the site. It discusses: i) the seismic response of the facility, more specifically, the surface manifestation of seismic soil liquefaction in the form of soil ejecta, ground deformations and displacements, mapped after the earthquake sequence, ii) the results of site investigation studies, performed prior to the events, iii) subsurface soil characterization of the site, iv) assessments of soil liquefaction triggering, v) analyses of liquefaction-induced ground settlements, lateral deformations and displacements, and vi) comparisons of them with those of the predicted. The case history performance documented herein, and the assessment results are believed to be useful in the development of case history-based predictive models for the assessment of liquefaction triggering and post-liquefaction ground deformations.
•Liquefaction manifestations observed in a Metallurgical Facility in Hatay.•Lateral displacements and settlements varied in the range of 5–31 cm and 5–88 cm.•Low plasticity silts and clays were predicted to be liquefied.•Volumetric settlements were predicted by Shamoto et al. (1998) and Cetin et al. (2009).•Lateral displacements were predicted by Hamada et al. (1986) and Youd et al. (2002).
A database, which consists of maximum and minimum void ratio limits and their range, particle size, distribution and shape characteristics, is compiled. More specifically, minimum and maximum void ...ratios (emin and emax) along with their range (emax-emin), particle roundness (R) and spherecity (S), fines content (FC), coefficient of uniformity (Cu), mean grain size (D50) data are compiled from natural cohesionless soils and reconstituted grained material (e.g.: rice, glass beads, mica) mixtures. The final dataset is composed of 636, mostly soil samples. Out of 636 samples, 496, 474 and 603 of them have emax, emin or emax-emin data, respectively. Similarly, for 593, 419, 171, 126 and 93 soils, D50, Cu, R, S and FC data exists, respectively. Not for every sample, USCS based soil classification designation is available, hence for the missing ones, soil classification is performed based on mean particle diameter-based classification as suggested by ASTM D2487 – 17: Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System) 1. The dataset consists of 19 silts and clays, 527 sands (357 fine sands, 153 medium sands, 17 coarse sands) and 47 gravels (44 fine gravels, 3 coarse gravels). A spreadsheet summary of the dataset is provided. This dataset is later used for the development of probability-based void ratio predictive models.
The evaluation liquefaction-induced excessive ground displacements of the approach embankments of the Karasu Bridge, as surveyed following the Pazarcik M7.8 and Ekinozu-Elbistan M7.6, ...Kahramanmaras-Turkiye earthquakes on February 6, 2023, is presented. The Karasu Bridge, located on the Karasu River, connects the metropolitan city of Hatay and the State Hospital. The approach embankments of the bridge are underlain by layers of low to high plasticity stiff clay and liquefaction susceptible clayey and silty medium dense sand units. Specifically, the non-plastic silty sands with fines contents ranging from 21% to 42%, were evaluated as the critical (liquefied) soil units during the Pazarcik earthquake. Liquefaction triggering assessments, following the procedure outlined by Cetin et al. (2018), estimated factor of safety against liquefaction <1.0, confirming the surface manifestations of liquefaction at the site. Empirical approaches suggested by Hamada et al. (1986) and Youd et al. (2002) predicted lateral ground displacements triggered by liquefaction, averaging 137 cm and 383 cm, respectively. These values are comparable with mapped lateral displacements, which exceeded 150 cm. Volumetric settlement assessments, utilizing the method outlined by Cetin et al. (2009), predicted 14 to 26 cm, approximately one third to half of the mapped settlement values ranging from 40 to 55 cm. The discrepancy is attributed to the three-dimensional nature of site behavior and induced deviatoric strains, contributing to additional settlements beyond the volumetric component.
•Liquefaction manifestations observed at approach embankments of the Karasu Bridge in Hatay.•Lateral displacements exceed 150 cm and settlements ranging from 40 to 55 cm.•Non plastic silty sands with fine contents ranging from 21% to 42% were predicted to be liquefied.•Liquefaction triggering assessments were predicted by Cetin et al. (2018).•Lateral displacements were predicted by Hamada et al. (1986) and Youd et al. (2002).•Volumetric settlements were predicted by Cetin et al. (2009).
The void ratio limits and their range are mostly governed by their grain size, distribution, particle shape and fabric for cohesionless soils. For the purpose of developing a probability-based ...predictive model, a database, which consists of minimum and maximum void ratios, their range, as well as particle morphology (roundness, sphericity), size and distribution (mean grain size, fines content and coefficient of uniformity) parameters, is compiled. A set of predictive models, which use the combinations of Cu, D50, FC, R, and S parameters, is proposed. The models with Cu and/or D50, R and S, produce the most precise predictions. The probabilistic forward use of the proposed models is illustrated by a practical example. They are also presented in the form of deterministic chart solutions, illustrating the variation of in-situ void ratios for varying density states as functions of uniformity coefficient or mean grain size.
•A database consisting of emax and emin, grain shape (R, S), size and distribution (D50, FC & Cu) parameters, is compiled.•Probability-based predictive models, which use the combinations of Cu, D50, FC, R, and S parameters are proposed.•Deterministic in-situ void ratio vs. Cu or D50 and DR chart solutions are presented.•The probabilistic forward use of the proposed models is illustrated with a practical example.
On January 24, 2020, Sivrice–Elazig–Turkey earthquake occurred along the East Anatolian Fault Zone. The moment magnitude of the event was reported as 6.8. This paper documents reconnaissance findings ...performed immediately after the event. Investigated sites namely, Lake Hazar shores, Karakaya Dam Reservoir–Euphrates River shores, Malatya–Battalgazi district and its villages, and Elazig Downtown are predicted to be shaken by rock peak ground acceleration, PGA
VS30=1100 m/s
, levels of 0.12–0.42 g, 0.05–0.11 g, 0.05 g, and 0.08 g respectively. The documented geotechnical field performances vary from widespread liquefaction-induced sand boils and lateral spreading, to no signs of surface manifestations of permanent ground deformations or soil liquefaction. In Battalgazi district and Elazig Downtown, the foundation performances vary from no signs of permanent ground deformations to 1–3 cm settlements, and 1–2 cm lateral movements. Additionally, the hydraulic structures inspected are estimated to be shaken by PGA
VS30=1100 m/s
levels of 0.03–0.23 g. Other than a minor longitudinal cracking along a limited section along the crest of a homogeneous earthfill dam, no apparent signs of permanent ground deformations were reported. Last but not least, a number of rock falls were mapped, based on back analyses of which probable peak ground velocities at these rockfall sites were speculated.
Due to the unique soil, morphological, and subsurface topographical conditions, amplified and prolonged seismic demand traces were observed in historical strong ground motion records from ...Bayrakli-Izmir-Turkiye. A vivid example of this response was recorded during the M
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7.0 Samos event on October 30, 2020. After the event, structural damage and loss of life were unexpectedly concentrated in Bayrakli-Izmir, even though the fault rupture was located 70 km away. The presence of strong ground motion stations (SGMS) located on rock (#3514) and soil (#3513) sites enabled a quantitative assessment of the amplified and prolonged seismic demand traces. The seismic response of SGMS #3513 site was assessed by using 1-D equivalent linear and analytical methods. The idealized 1-D soil profile and input parameters were calibrated and fine-tuned by using the 2020 Samos earthquake accelerograms. Then, the calibrated equivalent linear site response model was further validated by the recordings from historical events. Alternatively, an analytical wave propagation-based model was proposed, the input parameters of which were probabilistically estimated based on, again, historical recordings. Finally, the seismic responses of the site during future earthquakes were predicted based on the calibrated and validated site response models. The predicted intensity-dependent amplification spectral responses were compared with the provisions of the TEC (2018). Even though limited in number in all five future seismic scenario events, amplification ratios suggested by TEC were exceeded by a factor of 2–4 at periods falling in the range of 0.5 to 1.2 s. This clearly suggested the need to further quantify the Bayrakli seismic basin responses with basin-specific models, rather than code-based, intensity-dependent generalized amplification factors.
Abstract Seismically induced soil liquefaction was listed as one of the major causes of damage observed in the natural and built environment during the 2023 Türkiye-Kahramanmaraş earthquake sequence. ...Reconnaissance field investigations were performed to collect perishable data and document the extent of damage immediately after the events. The sites with surface manifestations of seismic soil liquefaction in the form of soil ejecta, excessive foundation and ground deformations were identified and documented. The deformations were mapped, and samples from ejecta were retrieved. The ejecta samples were predominantly classified as sands with varying degrees of fines. Laboratory test results performed on liquefied soil ejecta revealed that the fines-containing liquefied ejecta samples are mostly classified as low plasticity clays (CL). Most of CL soil type ejecta were retrieved from Gölbaşı–Adıyaman region. The liquid limits of these samples varied in between 32 and 38%, their plasticity index values were estimated in the range of 16–23%. Surprisingly, two ejecta samples with plasticity indices higher than 30% were retrieved from Hatay airport, one of which was classified as high plasticity clay (CH). The majority of the fine-grained ejecta samples fall either on “Zone B: Testing Recommended” region of the Seed et al. (Keynote presentation, 26th Annual ASCE Los Angeles Geotechnical Spring Seminar, Long Beach, CA, 2003) susceptibility chart. Moreover, 12 out of 74 samples fall outside the susceptible limits defined by Seed et. These preliminary results suggest that clayey soils can produce liquefied ejecta when subjected to cyclic loading. Detailed site investigation and laboratory testing programs are ongoing to further investigate this rather unexpected response. Until their findings become available, the liquefaction susceptibility of silty-clayey soils’ mixtures is recommended to be assessed conservatively with caution.
On February 6, 2023, two devastating earthquakes occurred on the East Anatolian Fault, Turkiye. The earthquakes had severe impacts on civil engineering structures in Iskenderun, Hatay. Reconnaissance ...studies were performed in Iskenderun to document and evaluate the performances of the different foundation systems and improved ground. Several soil liquefaction cases, including a boulevard, a mosque complex, fishing shelter, and military quarters were observed and documented along with the ground conditions and surface ejecta characteristics. The site observations during the reconnaissance study showed that the application of the unreinforced concrete piles was not a proper foundation solution against seismic loading and did not perform well. Whereas foundation systems including reinforced barrette piles and improved sites with jet grout columns were observed to perform quite well with negligible/no deformations. Observations at several structures indicate that conventional pile foundations also performed well, however structures built on deep foundation systems together with prior jet grout improved sites performed notably better.
•February 6 earthquakes had severe impacts on engineering structures in Iskenderun.•This is a reconnaissance study which discusses liquefaction cases in Iskenderun.•Additionally, seismic performance of various foundation systems were evaluated.•28 buildings were evaluated in-terms of foundation type and the observed damage.•Structures supported by deep foundations and ground improvement performed notably better.
During the October 30, 2020 M
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7.0 Samos Earthquake, the Turkiye-Izmir-Bayrakli district was affected the most due to the geometry and the deep-soft alluvial nature of the basin, although the ...district is approximately 70 km away from the epicenter. In this study, the seismic response of the Bayrakli basin, and the role of the soil stratigraphy and basin geometry on the recorded amplifications and prolonging of seismic shakings are investigated by using 1-, 2- and 3-D non-linear finite element-based dynamic response analyses. The assessment results are presented in the form of spectral amplification ratios,
A
T
. The highest
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values were estimated at spectral periods T = 0.85 and 1 s. They exceed five in both the east–west and the north–south directions, more pronounced in the latter one.
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was decomposed into the product of two independent amplification factors, namely rock to soil amplifications,
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, and 1-D soil column to 3-D soil basin amplifications,
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.
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values for T = 0.85 and 1 s are estimated as high as 1.4 and 1.6, in the east–west and the north–south directions, respectively. These values suggest that the 3-D geometry of the Bayrakli basin amplifies the spectral accelerations by 40–60% at T = 0.85 and 1 s. The unique combination of a deep-soft alluvial site with 3-D basin geometry, and overlying 7–9 story residential buildings, consistently favors and amplifies the seismic energy in the spectral period range of 0.7–1.0 s. This multi-fold increased seismic demand, combined with poor structural design and construction details, lead to localized structural damage and over 117 life losses.
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