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Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2026/r/gumushane/19452
  Gümüşhane’nin Heyelan Duyarlılığının Makine Öğrenmesi Algoritmaları Kullanılarak Değerlendirilmesi

  Bostancı, Hasan Tahsin

  Gümüşhane, jeolojik yapısı, engebeli topografyası ve iklimsel özellikleri nedeniyle ülkemizde heyelan, kaya düşmesi ve çığ gibi kütle hareketlerinin sıkça yaşandığı illerden biridir. 2021 yılında hazırlanan il afet risk azaltma planında il genelinde meydana gelen doğal afetlerin %49’unu heyelanların oluşturduğu belirtilmiştir. Dolayısıyla bu çalışmada, makine öğrenmesi algoritmaları kullanılarak Gümüşhane’nin Merkez ilçesinin heyelan duyarlılık haritalarının üretilmesi amaçlanmıştır. Çalışmada makine öğrenmesi algoritmaları olarak lojistik regresyon (LR), yapay sinir ağları (ANN) ve destek vektör makineleri (SVM) tercih edilmiştir. Adı geçen algoritmalarla oluşturulan duyarlılık modellerinde; bakı, drenaj ağlarına uzaklık, yola uzaklık, yükseklik, arazi örtüsü, litoloji, plan eğriliği, profil eğriliği, eğim ve topografik nemlilik indeksi (TWI)’nden oluşan 10 faktör kullanılmıştır. Modellerin eğitim ve doğrulama aşamasında MTA Genel Müdürlüğünden temin edilen heyelan envanter haritası kullanılmıştır. LR, ANN ve SVM modellerinin performansı ROC eğrisi altında kalan alan (area under the ROC curve - AUC) metriği kullanılarak değerlendirilmiştir. LR, ANN ve SVM modellerinin AUC değerleri, sırasıyla, 0.784, 0.865 ve 0.888 olarak belirlenmiştir. Bu sonuçlar SVM modelinin diğer modellerden daha iyi performans gösterdiğini ortaya koymuştur. Ayrıca, çalışma alanında heyelanların meydana gelmesinde en etkili faktörlerin sırasıyla eğim, yükseklik, TWI ve yola yakınlık olduğu belirlenmiştir. 

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• MakaleAçık Erişim2024/r/gumushane/13960
  Monitoring Surface Deformations in a Fossil Landslide Zone and Identifying Potential Failure Mechanisms: A Case Study of Gümüşhane State Hospital

  Alemdag, Selçuk; Yalvaç, Sefa; Bjelotomić Oršulić, Olga; Kara, Osman; Zeybek, Halil İbrahim; Bostanci, Hasan Tahsin; Markovinović, Danko

  The escalating occurrence of landslides has drawn increasing attention from the scientific community, primarily driven by a combination of natural phenomena such as unpredictable seismic events, intensified precipitation, and rapid snowmelt attributable to climate fluctuations, compounded by inadequacies in engineering practices during site selection. Within the scope of this investigation, contemporary geodetic techniques using the GNSS were employed to monitor structural and surface deformations in and around a hospital edifice situated within an ancient fossil landslide region. Additionally, inclinometer measurements facilitated the determination of slip circle parameters. A subsequent analysis integrated these datasets to scrutinize both the hospital structure and its surrounding slopes. In addition to the finite element method, four different limit equilibrium methods (Bishop, GLE–Morgenstern–Price, Spencer, and Janbu) were used in the evaluation of stability. Since the safety number determined in all analyses was <1, it was determined that the slope containing the hospital building was unstable. The movement has occurred again due to the additional load created by the hospital building built on the currently stable slope, the effect of surface and groundwater, and the improperly designed road route. As a result of geodetic monitoring, it was determined that the sliding speed on the surface was in the N-E direction and was approximately 3 cm, and this situation almost coincided with inclinometer measurements.

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• MakaleAçık Erişim2022/r/gumushane/14970
  Evaluation of potential rock falls with three-dimensional analysis: Example of Oltanbey and Hasanbey districts (Gümüşhane city center)

  Alemdağ, Selçuk; Kara, Rasim Taylan; Bostanci, Hasan Tahsin

  The central district campus of Gümüşhane, located on the Trabzon-Erzurum Highway, has a steep topography, and because of the effect of climatic and morphological structure, frequent rockfall events can cause loss of life and property from time to time. For these reasons, the slopes in some parts of the Oltanbey and Hasanbey districts of the central district of Gümüşhane, which pose a great threat in terms of rockfall potential, were chosen as the study area. In this study, three-dimensional rockfall analyzes were carried out using the RocPro3D program on the lines determined in the rockfall source zones with a high probability of rockfall. As a result of the analysis, it was determined that the rock blocks rolled from the O1, O2 and H1 source rock lines determined at the upper elevations of the study area threaten the settlements and road networks in Oltanbey and Hasanbey districts. With the 3D rockfall analysis, steel barrier was applied as a precautionary structure in the areas determined to be under the risk of rockfall, and the analyzes were carried out again considering the precautionary structures. By examining the results of the analyzes, the safest and most economical different barrier types have been proposed to eliminate the danger of rockfall.

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• MakaleYalnız künye2022/r/gumushane/14884
  GIS-based determination of potential instabilities and source rock areas on the Torul-Kürtün (Gümüşhane) motorway, rockfall, and protection structure analyses

  Alemdag, Selcuk; Bostanci, Hasan Tahsin; Gacener, Elif

  The Torul-Kürtün-Tirebolu motorway, one of the alternative routes for access between the Eastern Anatolia Region and the Black Sea Region, has an important traffic potential in this respect. However, rockfall events that occur frequently in almost every season especially in the part of the route between Torul and Kürtün may occasionally cause loss of life and property and lead to disruption in transportation in a much more common way. Departing from this point, the parts of the motorway that pose a greater threat in terms of slope instability and rockfall potential were selected as the study area. Instability maps produced by the kinematic analysis results showed that the probability of toppling type failure in the study area was quite higher, while the general results were as follows: the probability of toppling type failure was found in 204 different locations and approximately 97,900 m2 of area. Taking account of geographic information system (GIS)–based final instability maps, profile lines were determined for potential rockfalls in the instability-intense source rock areas. The profile lines which were determined were analyzed two-dimensionally in the RocFall 7.0 computer program. The rockfall analyses revealed that the rolling rock blocks in the section SP7 shall remain on the surface of the slope, while the rock blocks in other sections shall reach the road route. The application of barrier types determined by barrier sensitivity analysis on profile lines will minimize or completely prevent potential hazards.

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• MakaleYalnız künye2020/r/gumushane/12891
  Medium scale earthflow susceptibility modelling by remote sensing and geographical information systems based multivariate statistics approach: an example from Northeastern Turkey

  Dağ, Serhat; Akgün, Aykut; Kaya, Ayberk; Alemdağ, Selçuk; Bostancı, Hasan Tahsin

  The aim of the present study was to produce an earthflow susceptibility map for the city center and environs of the province of Rize located at the Northeastern part of Turkey. The study area is the rainiest region of Turkey, and due to the triggering effect of precipitation earthflows are frequently observed in and around the study area. Besides this point, weathered rock units and steep topography accompany with precipitation for the occurrence of earthflow cases. Considering this point, an earthflow susceptibility mapping was inferred to be a necessity for the area. Parameters, such as lithology, slope gradient, slope aspect, topographical wetness index (TWI), stream power index (SPI), slope curvature, and sediment capacity index (LS) were considered to be earthflow conditioning parameters. A multi-temporal earthflow inventory map for a period of 4 years (2011–2015) was initially generated by way of remote sensing approach and field surveys. Earthflow susceptibility map was produced using the logistic regression method after which the produced susceptibility map was validated. The mapped earthflows were separated into two groups prior to modelling and validation. The first group was for training and the second group was for validation steps. The accuracy of the model was measured by fitting them to a validation set of mapped earthflows. Area under curvature (AUC) approach was applied for validation purposes. The prediction capability of the earthflow susceptibility map produced can be regarded as acceptable in accordance with the AUC values of 0.62 for the logistic regression model. Based on these results, the obtained earthflow susceptibility map can be used to mitigate hazards related to landslides and to aid in land-use planning for the Rize city center.

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• MakaleAçık Erişim2018/r/gumushane/12361
  Combination of discontinuity characteristics and GIS for regional assessment of natural rock slopes in a mountainous area (NE Turkey)

  Bostanci, Hasan Tahsin; Alemdag, Selcuk; Gurocak, Zulfu; Gokceoglu, Candan

  Geographical Information Systems (GIS) have a very large spectrum of users. As in many engineering applications, GIS are frequently used in geotechnical projects, especially in producing various thematic and zoning maps such as various susceptibility and hazard maps. Instability maps for large areas with similar characteristic can be produced in a practical way by evaluating the results obtained by the data collected from field and laboratory studies. In order to introduce a methodology for producing rock slope instability maps for a large area, discontinuity controlled slope failures in the Köse Granitoid Complex (NE Turkey) were selected. To determine the types of failure such as planar, wedge, and toppling, and possible instable slope orientations kinematic analyses were carried out in the limited areas. The relationships between orientations of natural slopes and discontinuities obtained from kinematic analyses were evaluated with GIS software. Finally, discontinuity controlled instability maps were produced for the study area. Resulting maps show that the most common type of failure is wedge type. Additionally, the distributions of unstable areas along road networks were determined. Various land use types such as agriculture, grassland, settlement, and forest were also classified in order to predict the possible effects of slope instabilities. The methodology introduced in this study indicates highly promising results for the assessment of rock slope instability in large areas.

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• Kitap BölümüAçık Erişim2017/r/gumushane/15038
  Discontinuity controlled slope failure zoning for a granitoid complex: A fuzzy approach

  Gurocak, Z.; Alemdag, S.; Bostanci, H.T.; Gokceoglu, C.

  Kinematic analysis is one of the most used methods to evaluate potential failures such as planar, wedge and toppling in rock slopes. To analyze possible failure types, orientations of slope and discontinuity geometry with the friction angle of the discontinuities planes are used. In this study, kinematical analyses were evaluated to obtain discontinuity controlled potential failure types in the Gumushane Granitoid Complex which is exposed in Gumushane City and the surroundings. Unstable slope orientations for planar, wedge and toppling failure types were determined. The unstable orientations obtained from kinematic analyses were used to create Geographic Information System (GIS) based instability risk maps. The maps generated by the GIS were evaluated using the Fuzzy Interference System (FIS) method to produce instability risk maps for the study area.

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