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The aim of the present study was to investigate the effects of the February 6, 2023, earthquakes in Turkey and recurrent aftershocks on balance and post-traumatic stress in surviving victims. Our study included 1004 participants aged 18–65 years who were exposed to the February 6 earthquakes and aftershocks in Turkey. After obtaining online consent from all participants, the Vertigo Symptom Scale (VSS), the Dizziness Handicap Index (DHI), and the Posttraumatic Post-Traumatic Disorder Checklist Scale (PCL-5) were administered online, and the interactions between the variable sets were examined using a correlational screening model. As a result of the structural equation model established with the observed variables, it was found that VSS total scores had a statistically significant positive effect on PCL-5 (β1 = 0.56; p = 0.001 < 0.05). In addition, statistically significant positive high-level correlations were found between VSS and DHI (cov VSS-DHI = 0.71), and a positive low level correlation with the number of days with dizziness (cov VSS-number of days with dizziness = 0.34), and a positive low level correlation with frequency of days with dizziness (cov VSS-frequency of days with dizziness = 0.37). A statistically significant positive low-level relationship was found between DHI and the number of days with dizziness (cov DHI-number of days with dizziness = 0.34) and a positive low-level correlation between DHI and the frequency of days with dizziness (cov DHI-frequency of days with dizziness = 0.29). The structural equation modeling analysis showed that post-traumatic stress disorder had a significant effect on balance and dizziness. [ABSTRACT FROM AUTHOR]

In the southeastern part of Turkey, two earthquakes measuring 7.7 and 7.8 on the Richter scale occurred within 9 h on 6 February 2023, causing 120,000 injuries and over 50,000 deaths. Evacuees were transferred to various secondary and tertiary hospitals as the health system and hospitals in the affected region were affected by the earthquake. Injuries were mostly caused by blunt trauma and/or prolonged bruising under rubble. The severity and pattern of traumatic injuries in earthquake victims differed from other trauma patients who were not affected by an earthquake. In addition to traumatic injuries that affected multiple body regions and systems, patients who were trapped under debris for long periods of time were also frequently found to have crush syndrome. Pulmonary thromboembolism and hypoxic–ischaemic brain injury were observed in some patients. In this review, we present the imaging findings of traumatic injuries in earthquake victims, emphasising the earthquake-related distinct injury types. [ABSTRACT FROM AUTHOR]

Turkey has large aggregate deposits; however, these deposits cannot be used effectively due to a lack of controls. This can lead to fatal errors, as in the 6 February 2023 Turkey-Syria earthquakes. The main motivation of this study is to investigate the availability of existing and new aggregate deposits as concrete aggregates in northeastern Turkey. Thus, the quality of aggregates in this region will be studied comparatively. This research was carried out with aggregate samples taken from 30 different rock quarries in 10 different provinces in this region of Turkey. First, the locations of 30 crushed rock aggregates were identified, and their petrographic, mineralogical, physical, geometric and durability properties were determined. Fifteen different test procedures were applied to 30 crushed rock samples. It was concluded that these rocks are generally sedimentary rock types and that 18 of these 30 samples are of limestone origin. To obtain high-strength concrete, in addition to quality cement, the aggregates used must also be of high quality. The use of aggregate resources mentioned in this study for building concrete will contribute to the production of high-strength concrete. These samples, which generally have sufficient physical, mechanical and durability properties, meet the limitations of the standards much better than concrete aggregates. High-statistical-performance regression equations were obtained for the physical and durability properties. • There are rich rock resources in northeast of Turkey that can be used as aggregate. • Igneous rocks are more resistant to freeze-thaw effects than sedimentary rocks. • Sedimentary rocks are more durable against freeze-thaw effects than igneous rocks. • Sedimentary rocks are more durable against ASR effects than igneous rocks. • Alkali resistance is higher for rocks that water absorption is smaller than 1 %. [ABSTRACT FROM AUTHOR]

Spike is a type of abnormal waveform observed in strong motion records. It is characterized by a sudden and significant increase in peak acceleration, exceeding the theoretical range, and being greatly uncoordinated with the surrounding record points. The spike severely affects the reliability of subsequent analysis of strong motion records. This paper conducts research based on the strong motion records of the Turkey-Syria earthquakes in 2023. It focuses on the spike represented as Peak Ground Acceleration (PGA) and proposes a spike recognition model for strong motion records using Bayesian-optimized Support Vector Machine (SVM). Firstly, a preprocessing method for strong motion records based on adaptive waveform scaling is proposed. This method enables the adaptive normalization of strong motion records with different scales, thereby eliminating the influence of different scales on the accuracy of manual annotations. Furthermore, a new method for characterizing strong motion records is proposed. It captures shape features (two-dimensional) through one-dimensional data, enabling the spatial distribution of strong motion records to be represented by a shape feature vector. Finally, a Bayesian optimization-based improved SVM model is proposed. It utilizes the feature extraction method proposed in this paper for the identification of spikes in strong motion records. The experimental results show that the proposed model in this paper achieved excellent performance, with an F1-score of 0.868 and an AUC value of 0.93 on the test set. • A normalization method for strong motion records at different scales is proposed. • Proposed a numerical computation-based method for spike feature extraction. • Developed a spike identification model based on Support Vector Machine. • Optimized our model's hyperparameters using bayesian optimization. • Achieved good results on the dataset of Turkey-Syria earthquakes. [ABSTRACT FROM AUTHOR]

While the structural deformation at the Arabia-Anatolia-Africa junction is critical for understanding eastern Mediterranean tectonics, it remains debatable (extensional or compressional). Field survey of the 2023 Mw7.7 Pazarcik earthquake surface rupture along the Amanos Range, and microstructure and composition analyses of related fault rock were performed to investigate this issue. The surface rupture shows transtensional branches, with the main and secondary strands displaying sinistral (normal) offsets of 2.0–4.0 (0.4–0.9) and 1.0 (0.2) m. Slip plane of the secondary fault is marked by a ∼20 cm wide extensional fracture dividing fault breccia from gouge. Meanwhile, the gouge (26 % calcite, 38% serpentine and 36% smectite) is also dominated by tension cracks microscopically. In contrast to the widespread extensional deformation, geological evidence imply that this fault had experienced reverse slip in the Quaternary, as shown by thrusting of serpentine onto alluvium and the consistency of R foliations with reverse shear. We interpret it as the SW continuation of the East Anatolia fault (EAF) that was formerly characterized by transpressional deformation, and reactivated transtensionally due to the change of fault strike during this earthquake. In the broader Mediterranean tectonics framework, the Amanos segment might be interpreted as a recently formed component linking the Karasu fault to the EAF. • The coseismic rupture along the Amanos Range is overall transtensional. • The largest branch fault reactivated was previously transpressional. • This transformation happened in the Quaternary. • It highlights the tectonic evolution in the Arabia-Anatolia-Africa junction zone. [ABSTRACT FROM AUTHOR]

• Significance of design errors in the structural system. • Steel retrofitting and load transfer elements applied in relatively few but logical places is remarkable. • Strengthening and load transfer improvement works beam damages were reduced by 40 % for X direction and 50 % for Y direction. • Life safety performance level ratio, which was 30.1 % in the ground floor columns, decreased to 13.5 %. On 6 February 2023, two large earthquakes of M w 7.7 and 7.6 occurred in the Pazarcik and Elbistan districts of Kahramanmaras province in Turkey, causing extensive structural damage, collapsed buildings and casualties. This study examines a damaged building and presents the relevant repair and strengthening procedures. The importance of design flaws in the structural system, particularly when subjected to horizontal and vertical ground motions, on the performance of the structure is highlighted in this case study. The effects of the interrupted frames and components with unsuitable cross-sectional properties for load transfer within the structure were comprehensively assessed using 3D modelling and on-site investigations. Following repair and strengthening works to improve load transfer, the analysis carried out on the model showed a reduction in LS of approximately 33 % for beams and 45 % for columns. [ABSTRACT FROM AUTHOR]

Residual drift of structural systems after seismic events can make buildings uninhabitable and may cause their collapse in aftershocks, as seen in the 2023 Turkey-Syria earthquake. Self-centering rocking-core systems can eliminate plastic deformation of structures after earthquakes. In the current study, a bi-rocking steel-braced frame was designed using the modified modal superposition (MMS) method. The optimal location of the secondary joint was found to minimize the base shear, overturning moment, peak floor acceleration and inter-story drift. Damage to non-structural components has been considered. The models included 12-, 18- and 24- story frames that were subjected to far-field (FF), near-field-pulse (NP) and near-field-no-pulse (N) ground motion records. The seismic records were scaled to the maximum credible earthquake level. Nonlinear time-history analyses were performed using OpenSees open-source finite element software. Additionally, post-tensioned cables and energy dissipation fuses as variable parameters were optimized using particle swarm optimization. The performance of seven metaheuristic algorithms was compared and the results showed that placing the secondary joint at the mid-height of the structure reduced all seismic demand. The results also suggest that the story moment and FF records were most sensitive to the location of the secondary joint. It was observed that frames with lower stiffness and yield strength of the damper exhibited better seismic performance. Based on this, corrective percentages have been proposed for the design of the cable and dampers. A self-centering ratio of 1.07 was suggested at the mid-height and 1.19 for the base damper. The colliding bodies optimization algorithm performed best for time-history analysis-based optimization. • Using a bi-rocking mechanism to reduce the higher mode effects of high-rise structures. • Designing the bi-rocking steel-braced frame with modified modal superposition method. • Optimization of the main design parameters of bi-rocking joints using metaheuristic algorithms. • Investigating the performance of the bi-rocking steel-braced frame under far- and near-field ground motions. [ABSTRACT FROM AUTHOR]