Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2024Damage assessment of Siverek Castle during the Kahramanmaraş Earthquakes (Mw 7.7 and Mw 7.6) on 06 February 2023: Remediation and strengthening proposals
Nasery, Mohammad Manzoor; Çelik, Muhammet; Şadoğlu, Erol
On February 6, 2023, two significant earthquakes with magnitudes (Mw) of 7.7 and 7.6 struck Turkey, occurring nine hours apart. In addition to the tragic loss of over 50,000 lives in the earthquakes centered in Kahramanmaraş, hundreds of thousands of engineering structures, such as residences, schools, hospitals, historical landmarks, highways, and more, were severely damaged. This study assesses the damages and risk scenario following the Kahramanmaraş earthquakes concerning Siverek Castle. In addition, remediation and strengthening proposals, required to eliminate the damage and the possible risk, have been developed. The initial stage involved observational damage assessments on the castle and surrounding slopes as part of field studies, identifying five different types of damage and potential risks. Subsequently, a precise 3D digital model of the damaged castle and its slopes was generated using the digital photogrammetry method. Additionally, geological and geophysical studies were conducted in the field to determine the characteristics of the mound structure, historical castle walls, soil and rock on the slope. Non-destructive, geophysical methods consisting Vertical Electrical Sounding (VES), Seismic Refraction Method (SRM) and Multichannel Analysis of Surface Waves (MASW) measurements were specifically employed in the area with historical remnants. To verify the obtained data, five boreholes were drilled in the lower parts of the slope, and experimental studies were conducted to determine the soil and rock material properties of the slope. In the numerical studies, a total of 54 2D stability analyses were performed under static, long-term static, and dynamic conditions. Additionally, 1000 different probabilistic rockfall analyses were conducted, both in 2D and 3D, to calculate the run-out distance, bounce height, velocity, and kinetic energies of the blocks that fell or were about to fall during the earthquake. In the final stage of the study, remediation and strengthening recommendations were prepared for the strengthening of the fortification walls and slopes where failures occurred, and stability analyses were conducted. Consequently, a design proposal recommending five distinct approaches to remediate and strengthen the castle and slopes impacted by the Kahramanmaraş earthquakes was endorsed by the relevant authorities, and construction has commenced. When the remediation and strengthening works are completed, the security of the cultural heritage will be ensured, and it is planned to be opened to visitors.
- MakaleYalnız künye2022Investigating 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.
- MakaleAçık Erişim2021Performance of AC overlays using geogrids on PCC contraction joints
Çelik, Muhammet; Seferoğlu, Mehmet Tevfik; Akpınar, Muhammet Vefa
It is widely known that vertical displacements and strains occur on the joints and these cause defects on the asphalt concrete (AC) overlays on existing Portland cement concrete (PCC) pavements. Various approaches were introduced to minimize these defects. In this study, the effect of joint support formed using the geogrid material with grout mortar on the vertical displacement of PCC and the strain at the bottom of the AC layer. Produced layers were exposed to 1,186,000 Equivalent Single Axle Load (ESAL) in an APT (Accelerated Pavement Test) facility and the results were monitored. According to the obtained results, the use of AC overlay reduces vertical displacement in the PCC by 75%. When geogrid reinforced AC overlay was used, an additional reduction in displacement by 41.2% was achieved. Geogrid reinforcement reduced strain values formed at the bottom of the AC layer from 29.5% to 92.5%. The use of geogrid at joints instead of increasing the thickness of the AC layer from 50 to 80 mm resulted a more significant reduction in both strain and displacement. Besides, the usage of a geogrid interlayer instead of increasing the thickness of the AC layer also provided a significant cost reduction of 57.9% in overall cost.
- MakaleAçık Erişim2020Plent-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.
- MakaleAçık Erişim2020Beton 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.
- MakaleAçık Erişim2020Effect 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.
- MakaleYalnız künye2020Economic 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.