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Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2025/r/gumushane/19668
  Kayseri’de otobüs ve tramvay hizmet kalitesi: Yolcu memnuniyetinin karşılaştırmalı bir analizi

  Seferoglu, Aysegul Gunes; Polat, Fatih

  Bu çalışma, Kayseri ilinde toplu taşımada kullanılan otobüs ve tramvay hizmetlerinin yolcular tarafından algılanan hizmet kalitesini değerlendirmek ve karşılaştırmak amacıyla gerçekleştirilmiştir. Çevrimiçi olarak uygulanan anket çalışması, demografik bilgiler ve hizmet kalitesi algısını ölçen 20 maddeden oluşmaktadır. Verilerin analizi SPSS 22.0 programı kullanılarak gerçekleştirilmiş; bağımsız grup t-testi, Levene testi ve tek yönlü ANOVA yöntemleri uygulanmıştır. Sonuçlara göre, tramvay kullanıcıları genel memnuniyet düzeyinde otobüs kullanıcılarına göre daha yüksek puan vermiştir. Tramvayda en yüksek memnuniyet, zamanında gelme ve ücret ödeme kolaylığı) alanlarında gözlenirken, doluluk oranı ve koltuk konforu gibi konularda memnuniyet daha düşüktür. Otobüs kullanıcıları genel memnuniyet açısından daha düşük puanlar vermiş; ancak ödeme kolaylığı ve alternatif hat bulma gibi alanlarda nispeten olumlu görüş bildirmiştir. Koltuk konforu ise en düşük memnuniyet alanı olmuştur. Demografik değişkenlerden sadece medeni durum ve eğitim düzeyine göre anlamlı fark bulunmuştur. Genel olarak, tramvay hizmetleri daha yüksek kalite algısı yaratmakta; ancak her iki sistemde de kapasite, sürücü davranışları ve planlama alanlarında iyileştirme gereksinimi ortaya çıkmıştır.

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• MakaleAçık Erişim2025/r/gumushane/12431
  Flexural Behavior and Sustainability of Dual-Waste Fiber-Reinforced Concrete Designed for Pavement Applications

  Seferoğlu, Mehmet Tevfik; Aksüt, Yavuz Selim; Seferoğlu, Ayşegül Güneş

  This study evaluates the mechanical performance and sustainability potential of fiber-reinforced concrete incorporating mine tailings as the fine aggregate and waste tire wire as the reinforcing fiber. The concrete mixtures contained 0.2%, 0.4%, and 0.6% waste tire wire with the natural fine aggregate replaced entirely with Pb-Zn-Cu tailings. The mixtures were tested for porosity, water absorption, compressive strength, splitting tensile strength, flexural strength, toughness, fracture energy, and ductility to assess their mechanical performance and durability. The mine tailings improved the microstructure and reduced water absorption, particularly with tire wire. Using waste tire wire improved the compressive, tensile, and flexural performance; in particular, W-6 showed a 18.2% rise in compressive strength and a more than twofold increase in flexural strength relative to the control mix. The flexural toughness and fracture energy rose by up to 161%, while the ductility peaked at a fiber content of 0.2%. These gains were attributed to fiber crack-bridging and post-cracking energy absorption. The dual-waste system also reduced porosity, improved durability, and demonstrated strong potential for rigid pavement applications such as highways, industrial yards, and airport runways that require high fatigue resistance and a long service life. Beyond technical performance, this approach offers a sustainable solution that lowers maintenance, reduces life-cycle costs, and aligns with circular economy principles.

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• MakaleYayıncıda açık erişim2025/r/gumushane/12336
  Assessing the reliability of the lightweight deflectometer test for compaction control in highway subbase layers through SPSS analysis

  Seferoğlu, Mehmet Tevfik; Seferoğlu, Ayşegül Güneş; Akpınar, Muhammet Vefa; Iribagiza, Divine

  The condition of the highway base/subbase layers is critical for the durability and performance of the road pavement. Compaction control plays an important role in determining the ability of these layers to support traffic loads, their strength and stability. Various methods are used to evaluate the compaction rate of subbase layers; such as nuclear density gauge (NDG) and sand cone. These methods also have their own limitations and difficulties. While the NDG test is used to determine the compaction percentages, the lightweight deflectometer (LWD) test is used as a relatively more practical, portable and non-destructive method to measure the surface stiffness modulus (Emod). In this study, the possibility of using the surface stiffness modulus obtained by the LWD test in the subbase layer instead of each other is investigated by establishing a correlation between the compaction percentages determined by the NDG test. To investigate how well the LWD results are in line with established methods, only correlation and regression analysis of SPSS software are focused on. Correlation analysis helped us assess the strength and direction of the relationships between LWD modulus values and compaction percentages, while regression analysis provided insights into the predictive capability of LWD in estimating compaction outcomes. These methods helped evaluate the reliability and accuracy of LWD as a compaction control tool, providing a deeper understanding of the role of LWD in highway subbase layer assessment.

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• MakaleAçık Erişim2023/r/gumushane/11995
  Investigation of the structural damage caused by blasting activities in tunnels to surrounding buildings: The case of Gümüşhane belt highway; [Tünellerde patlatma faaliyetlerinin çevre binalara verdiği yapısal hasarın incelenmesi: Gümüşhane çevre yolu örneği]

  Seferoğlu, Mehmet Tevfik; Seferoğlu, Ayşegül Güneş; Akaryali, Enver

  Tunnels are road transport structures that reduce traffic and expropriation problems, noise, and possible damage to animals and plants, and provide safer, more comfortable, and faster transportation for vehicles compared to highways. However, some environmental problems occur during tunnel construction. These problems such as vibration, noise, rock throwing, etc. caused by the blasting process used during tunnel excavation on buildings and people should be well investigated. In this study, two buildings located close to the exit and entrance of two tunnels (T2 and T3 tunnels) on the Gümüşhane belt road were chosen to investigate. Firstly, the existing damages in the first building, which is 7 m away from the T2 tunnel exit, and the second building, which is 60 m away from the T3 tunnel entrance, were analyzed by considering criteria such as the geological and ground condition of the land and the building materials used during the construction of those building. In addition, the negative effects on the buildings were evaluated by calculating the vibrations after the blasting process in the tunnel with the help of various empirical formulas. Investigation on site showed that building 1 was built of masonry and building 2 was built of reinforced concrete, and that deep cracks had formed in the bearing systems of both buildings, spills occurred in the walls, and fractures in the windows. Also, calculations with empirical formulas showed that the vibration rates caused by blasting process in the 1st and 2nd buildings were as 385.68 mm/sec and 6.91 mm/sec, respectively, and these vibration values were above the standard values. The data obtained through examination on-site and empirical approaches show that it would be dangerous for people to be resident in both buildings.

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• MakaleYalnız künye2022/r/gumushane/15891
  Investigating the Influence of Joint Reinforcements of Portland Cement Concrete Slabs Under Asphalt Concrete Overlays on Vertical Deflections Using Accelerated Pavement Testing

  Seferoglu, Mehmet Tevfik; Seferoglu, Aysegul Gunes; Çelik, Muhammet; Akpinar, Muhammet Vefa

  Joint gaps between slabs in underlying Portland cement concrete (PCC) pavements are critical factors in the life span of asphalt concrete (AC) overlays. Therefore, being informed about the vertical deflections that may occur around the joints is important. In this study the joints were reinforced with three different materials: ethylene propylene diene monomer (i.e., rubber joint filler [RJF] reinforcement), bitumen-based sealant (i.e., rubber plate [RP] reinforcement), and steel plate (SP) (i.e., SP reinforcement), to limit the vertical movement of the underlying PCC. Tests were conducted at the accelerated pavement testing facility for two different AC overlay thicknesses, 50 mm and 100 mm, during 100,000 passages to investigate the influence of AC overlay thickness variations on slab vertical deflections and to also evaluate types of joint reinforcement on slab vertical deflections. For 50-mm thick AC overlay, the most effective joint reinforcements to prevent deformations caused by loading were RP, RJF, and SP; for a 100-mm thickness, this was determined to be RJF, SP, and RP, respectively.

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• MakaleAçık Erişim2021/r/gumushane/14573
  Evaluation of Load-Transfer Efficiency of Steel Mesh Reinforced Contraction Joints in Concrete Pavement: Accelerated Pavement Test and FE Analysis

  Celik, Muhammet; Seferoglu, Mehmet Tevfik; Akpinar, Muhammet Vefa; Nasery, Mohammad Manzoor; Seferoglu, Aysegul Gunes

  Transverse contraction joints are by far the most common type of joint in jointed plain concrete pavements. Early loading of contraction joints can create a weakened vertical plane and later grow as a full-depth crack. In this study, load transfer efficiency (LTE) of steel mesh reinforced transverse contraction joints were studied at accelerated pavement tests (APT). 3D finite element (FE) model of jointed plain concrete pavement (JPCP) was developed to study deflections and crack propagation in just under the joint of the concrete pavement. The APT tests were focused on the LTE values before and after the crack initiation under the contraction joint region. Experiments were performed on three slabs in which two of these slabs were prepared without reinforcement and one of them was reinforced with steel mesh. Data generated by APT was used for verification of crack propagation modeling in the finite element analysis. Steel mesh reinforced slab gave the lowest vertical deflections (51μm) and highest LTE (91.56%). The LTE value in the reinforced slab after 25,000 passes was 13.63% higher than the average of unreinforced slabs. The findings suggest that the load transfer efficiency was found to be a complex parameter and should be interpreted together with average displacement values when contraction joints are evaluated at early traffic loadings.

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• MakaleYalnız künye2020/r/gumushane/16283
  Economic Analysis of the Use of Reclaimed Asphalt Pavement (RAP) Materials in Plant-Mix Base Courses

  Seferoglu, Aysegul Gunes; Seferoglu, Mehmet Tevfik; Akpinar, Muhammet Vefa; Çelik, Muhammet

  The aim of this study is to determine the financial benefits to be gained based on the percentages of reclaimed asphalt pavement (RAP) material suitable for use in plent-mix courses (PBCs) to be designed according to the specification of Turkey Department of Transportation. Cost analysis of all RAP mixtures were made considering the construction of the plant-mix base course and the transportation costs of the materials, it was researched that the use of RAP would be an economical application in terms of how far the RAP material was taken. As a result of the study, it has been determined that the use of 100% RAP material in PBC is possible with cement reinforcement and it provides a profit of more than 16% in terms of costs in case of using virgin aggregate (VA) instead. RAP material is an alternative to virgin aggregate and is a more economical material in terms of cost.

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• MakaleAçık Erişim2020/r/gumushane/17754
  Plent-miks temel tabakası yapımında kazınmış asfalt kaplama (RAP) malzemesi kullanımı ve ekonomik analizi

  Seferoglu, Aysegul Gunes; Seferoglu, Mehmet Tevfik; Akpınar, Muhammet; Çelik, Muhammet

  Bu çalışmanın amacı, Karayolu Teknik Şartnamesi (KTŞ) kriterlerine göre tasarımı yapılacak olan bir plent-miks temel (PMT)tabakası için kullanılabilir kazınmış asfalt kaplama (RAP) malzemesi oranlarına bağlı olarak elde edilecek mali faydalarınbelirlenmesidir. Tüm RAP katkılı karışımların fayda-maliyet analizleri yapılarak PMT tabakası yapımı ve malzemelerin nakliyeharcamaları göz önüne alındığında, RAP malzemesinin hangi uzaklıktan getirilmesi durumunda ekonomik bir uygulama olacağıaraştırılmıştır. Çalışma neticesinde RAP malzemesinin %100 oranında PMT tabakalarında kullanımının çimento takviyesi ilemümkün olduğu ve doğal agrega (DA) yerine kullanılması durumunda %16’nın üzerinde kâr sağladığı belirlenmiştir. RAPmalzemesinin, PMT Tip-1 tabakası için doğal agregaya alternatif ve maliyet açısından daha ekonomik bir malzeme olduğusonucuna varılmıştır.

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• MakaleAçık Erişim2020/r/gumushane/16936
  Beton Yol Uygulamalarında Derz Türlerine Göre Düşey Deplasman Oluşumlarının İncelenmesi ve Maliyet Analizi: Trabzon-Rize Örneği

  Akpinar, Muhammet Vefa; Seferoğlu, Mehmet Tevfik; Güneş Seferoğlu, Ayşegül; Çelik, Muhammet

  Türkiye'de beton yolların kullanımı her geçen gün artmaktadır. Özellikle Doğu Karadeniz Bölgesi'nde 10.000 km'nin üzerinde beton yol bulunmaktadır. Bu çalışmada, Trabzon ve Rize İllerinde yapılan beton yol uygulamaları incelenerek yaygın olarak kullanılan kaplama kalınlığı ve beton basınç dayanımı belirlenmiştir. Karadeniz Teknik Üniversitesi Hızlandırılmış Yol Tesisinde örnek kaplama modeli hazırlanmış ve gerçek trafik yüklemeleri altında beton kaplamaların düşey deplasman değişimleri incelenmiştir. Farklı derz türleri (hasır donatılı yarım derz, donatısız yarım derz, dolgulu tam derz ve dolgusuz tam derz) kullanılarak fayda ve maliyet analizi yapılmıştır. Elde edilen verilere göre, derzlerin yarım derz olması ve kaplamada donatı kullanılması, donatısız yarım derzlere göre 1.3 kat, dolgulu tam derze göre yaklaşık 4 kat, dolgusuz tam derzlere göre ise yaklaşık 9 kat daha az düşey deplasman oluşmasını sağlamaktadır. Ayrıca yapılan maliyet analizlerine göre kaplamalarda hasır donatının bulunması, beton kaplama maliyetine km’de 38.002,76 TL (%11,6) fiyat farkı oluşturmaktadır. Bu bilgiler ışığında, beton kaplamalarda yarım derz yapılmasının ve hasır donatının kullanılmasının kaplama derz bölgelerindeki faydasına oranla maliyetinin oldukça düşük olduğu sonucuna ulaşılmıştır. Ayrıca mevcut tam derzli beton yollarda %7'lik ilave bir maliyet ile derzlerin içinin bitüm esaslı dolgu malzemesi ve kauçuk levhalarla kaplanmasının, düşey deplasman değerlerini en az yarı yarıya azaltılabileceği ve bu sayede kaplama ömrünün uzatılabileceği tespit edilmiştir.

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• MakaleAçık Erişim2020/r/gumushane/16293
  Effect of filler percentage of recycled asphalt pavement (RAP) materials on CBR performance and cost analysis

  Seferoglu, Aysegul Gunes; Seferoglu, Mehmet Tevfik; Akpinar, Muhammet Vefa; Çelik, Muhammet

  Recycled asphalt pavement (RAP) materials are an alternative to natural aggregate (NA) because they reduce environmental pollution and provide energy and cost savings. In many countries abroad, the usage of RAP materials in road pavement layers are permissible at certain rates. However, the mechanical properties of RAP materials are dependent on; the materials are derived from the in which pavement layer, the service life and construction characteristics of the road it is milled, the properties of the materials used (bitumen and aggregate) in the layer and the characteristics of the milling machine. In this study, two types of RAP materials (RAP(1) and RAP(2)) obtained from the degraded wearing layers of two different roadway using milling machine were mixed with NA in different rates (0%, 15%, 30%, 45%, 60%, 100%). Some of the characteristics of the mixtures were examined with reference to 100% NA mixture values by performing laboratory tests such as bitumen ratio, sieve analysis, modified proctor and California bearing ratio (CBR) on the mixtures obtained. According to the results, maximum rates of RAP(1) and RAP(2) which can be used in plant-mix base type-1 layer as an alternative material to NA is determined according to Turkey Highway Technical Specification. In addition, in the case of using RAP materials, the profit rates of material costs to be reduced by the reduction of the need for NA material are also determined by cost analysis.

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