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Öğe Bor nitrür ile güçlendirilmiş yağ asidi amid katkısının asfalt modifikasyonunda kullanılabilirliğinin araştırılması(Bursa Teknik Üniversitesi, 2024) Özdemir, Ahmet Münir; Yılmaz, BahadırEsnek üstyapılar, aşırı ve tekrarlı trafik yükleri, sıcaklık değişimleri, tasarım hataları, ultraviole ışınlar, çevresel ve kimyasal etkiler gibi sebeplerden dolayı bozulmaya uğramaktadırlar. Söz konusu bozulmalardan büyük oranda asfalt bağlayıcı sorumlu olup viskoelastik ve termoplastik yapısı onu bozulmalara karşı zayıf kılmaktadır. Asfalt bağlayıcının istenilen davranışta ve performans seviyesinde olması amacıyla çeşitli katkı maddeleri kullanılarak modifikasyonu sağlanmaktadır. Bu çalışmada atık hayvansal yağın diamin yapılarıyla rejenere edilmesiyle elde edilen katkı maddesinin asfalt bağlayıcı ve karışımı üzerindeki etkileri araştırılmıştır. Katkı maddesine termal özelliklerini ve yapısal stabilitesini artırmak amacıyla hekzagonal bor nitrür ilave edilmiştir. Bor nitrür takviyeli yağ asidi diaminleri ve bu maddenin asfalt bağlayıcıya muhtelif oranlarda ve uygun şartlarda ilave edilmesi sonrası elde edilen modifiye bağlayıcılar ve karışımlar üzerinde bir dizi laboratuvar çalışması gerçekleştirilmiştir. Sentezlenen katkı maddesinin yapısal karakterizasyonu, Nükleer Manyetik Rezonans (NMR), Fourier Dönüşümü Kızılötesi Spektroskopisi (FT-IR) ve Termogravimetrik (TG) analiz yöntemleri ile ortaya konulmuştur. Modifiye bağlayıcıların morfolojik özelliklerini belirlemek amacıyla Taramalı Elektron Mikroskobu (SEM), modifikasyon mekanizması ve termal performanslarını belirlemek amacıyla FT-IR ve TG analizleri gerçekleştirilmiştir. Bağlayıcılar üzerinde Dinamik Kayma Reometrisi (DSR), Dönel İnce Film Halinde Yaşlandırma (RTFOT), Dönel Viskozimetre (RV), Basınçlı Yaşlandırma Kabini (PAV), Eğilme Kirişi Reometrisi (BBR) ve geleneksel bağlayıcı deneyleri uygulanmıştır. Marshall dizayn yöntemine göre hazırlanan karşımlar üzerinde Marshall Stabilite ve Akma, Dolaylı Çekme, Su Hasarı, Dolaylı Çekme Mukavemeti, Statik Sünme, Dinamik (Tekrarlı) Sünme, Dolaylı (İndirek) Çekme Yorulma ve Nicholson Soyulma deneyleri uygulanmıştır. Sonuçlar, katkı maddesinin asfaltın kıvamını, kalıcı deformasyon dayanımını, yaşlanma ve yorulma direncini, esneklik ve yük taşıma kabiliyetini, soyulma direncini ve adezyon performansını, düşük sıcaklık dayanımını artırdığı belirlenmiştir. Katkı içerisindeki ideal bor nitrür oranının %10 olduğu, asfalt modifikasyonu için ideal katkı oranının ise %2 olduğu tespit edilmiştir. Bor nitrürürün asfalt ağırlığınca oldukça düşük bir miktarının asfalt performansı üzerindeki etkisi tatmin edici düzeydedir.Öğe Comparing Traffic Performances Between Signalized and Give-Way Roundabouts: A Case Study in Bursa(2023) Kayacan, Muhammed Alphan; Yılmaz, Bahadır; Özdemir, Ahmet MünirGlobally developing economies and opportunities have caused an increase in the density of people in city centers in recent years; thus, an exponential increase has been experienced in the number of motor vehicles, which complicates the creation of a sustainable traffic network. Waiting times and the number of stops cause psychological, physical, and environmental problems. The efficiency of intersections is vital to ensure sustainable transportation. Modern roundabouts outperform signalized roundabouts, and their popularity has been increasing in recent years. However, the geometric features of intersections should be suitable for the location and traffic composition. In this study, the Durmazlar roundabout, which is currently a signalized roundabout in Bursa, has been transformed into a modern roundabout and redesigned. One of the aims of the study is to make minimal changes in the geometry of the roundabout. One-way road applications have been made to regulate entrances and exits on problematic roads. Modeling of the roundabout and collecting data was performed through the PTV Vissim software. Queue length, travel time, and speed parameters of the data obtained regarding the new scenario and the current situation were compared.Öğe Dynamic-Mechanic Analysis and Rheological Modelling of Waste Face Mask Modified Bitumen(2024) Özdemir, Ahmet Münir; Yalçın, Erkut; Yılmaz, Mehmet; Kök, Baha VuralDue to the Covid-19 global pandemic, the use of face masks has increased considerably in recent years. Used face masks are released into our environment and become a severe environmental threat. Therefore, researchers have focused on the recycling of waste face masks. Recently, studies have been carried out on the use of waste face masks as additives in bituminous materials, but a detailed rheological characterization has not been made. In this study, modified bitumens were obtained by adding 1%, 1.5%, 2%, 2.5%, and 3% waste face mask (WFM). Subsequently, frequency sweep test was performed on modified bitumen samples through a Dynamic Shear Rheometer (DSR). Thus, the viscoelastic behavior of WFM modified bitumen was investigated at different temperatures and loading rates. Performance analysis was conducted with rheological master curves, which were characterized according to analytical and mechanistic models. In this study, rheological evaluations were performed according to the Christensen-Anderson (CA) Model, Christensen-Anderson-Marasteanu (CAM) Model, Sigmoidal Model (SM), and finally, the mechanistic Huet-Sayegh Model (HSM). According to the results, it was determined that WFM significantly increased the rutting resistance of bitumen and performed better at low and high loading rates than the pure bitumen at each WFM ratio.Öğe Farklı çentik derinliklerine sahip asfalt karışımlarının orta sıcaklıklarda kırılma özelliklerinin incelenmesi: Sonlu elemanlar yaklaşımı(2024) Özdemir, Ahmet Münir; Yalçın, Erkut; Yılmaz, Mehmet; Yılmaz, BahadırSon zamanlarda araştırmacılar, sonlu elemanlar yöntemini kullanarak asfalt karışımlarının çeşitli özelliklerini araştırmaya odaklanmışlardır. Bu yöntem sayesinde laboratuvarda performans testlerini simüle etmek ve çok benzer sonuçlar elde etmek mümkündür. Bu çalışmada, laboratuvarda yarı dairesel asfalt karışım numuneleri alınmış ve daha sonra kırılma parametrelerinin belirlenmesi için Yarım Daire Eğilme (SCB) testine tabi tutulmuştur. Sonlu elemanlar yazılımı yardımıyla 1 cm, 1.5 cm, 2 cm, 2.5 cm ve 3 cm olmak üzere beş farklı çentik derinliğinde 2 boyutlu asfalt karışım numuneleri oluşturulmuştur. Çentik derinliğinin asfalt karışımlarının kırılma özellikleri üzerindeki etkisi, 0.1, 0.5, 1, 5 ve 10 mm/dk.'lık beş farklı yer değiştirme hızında SCB testi simüle edilerek değerlendirilmiştir. Sonuçlar, çentik derinliği arttıkça maksimum yük ve kırılma enerjisi değerlerinin azaldığını göstermiştir. Ayrıca, elastik-plastik kırılma mekaniği yaklaşımı (J-integral) kullanılarak asfalt karışımlarının çatlak mukavemeti hesaplanmıştır. Son olarak, farklı değişkenlerin sonuçlar üzerindeki etki derecesini belirlemek için Tepki Yüzey Metodolojisi (RSM) analizi yapılmıştır. Sonuç olarak, çentik derinliğinin, yer değiştirme oranından daha önemli olduğu belirlenmiştir.Öğe Investigation of flow properties and activation energy of magnesium lignosulfonate modified bitumen(2023) Özdemir, Ahmet Münir; Yılmaz, BahadırRecently, many studies have been carried out on the use of waste materials in bitumen modification. In this way, environmental and economic benefits are obtained and a field of use is created for waste materials. In this study, magnesium lignosulfonate (MLS), which is an organic waste material released during paper production from wood, was added to B50/70 bitumen. Penetration, softening point, rolling thin film oven test (RTFOT) and rotational viscometer (RV) tests were performed on modified binders. As a result of the experiments, it was determined that MLS increased the consistency, softening point and short-term aging resistance of the asphalt and decreased the temperature sensitivity. In addition, the activation energy values were determined using the Arrhenius equation and the flow properties were evaluated.Öğe INVESTIGATION OF THE EFFECT OF CARBONATION CAKE ON RHEOLOGICAL PROPERTIES OF BITUMINOUS BINDERS(Necip Fazıl YILMAZ, 2021) Özdemir, Ahmet Münir; Yalçın, Erkut; Arslanoğlu, Hasan; Yilmaz, Mehmet; Kök, BahaAggregates and bitumen used in road flexible pavements are non-renewable natural materials and in terms of sustainability, it is of great importance that the service life of road pavements is long. Waste materials are also rising with increasing products due to industrial development. The evaluation of waste materials both prevents the destruction of nature by reducing the use of very limited natural materials and reduces the environmental problems in case of storage of waste materials. In this study, carbonation cake, which is a waste of sugar factory, was added to bitumen. Penetration, softening point, rotational viscosity and dynamic shear rheometer tests were applied on pure and modified bitumen. According to the results, it was determined that carbonation cake had no positive or negative effect on medium and high temperature rheological properties of bitumen. From the experiments, promising results have been obtained for the disposal of waste carbonation cake in a different area.Öğe Obtaining and modeling the relaxation modulus of self-healing asphalt mixtures(Fırat University, 2022) Yılmaz, Bahadır; Özdemir, Ahmet MünirIn this study, pure and self-healing asphalt mixture samples were obtained by adding capsules containing waste vegetable oil to mixtures at 0.25, 0.50, 0.75 and 1.00% ratios. Afterwards, creep test with a constant stress was carried out on the samples, and the resistance of asphalt mixtures against permanent deformation was investigated. Relaxation modulus values were obtained by using the creep compliance values that measured at the end of the experiment with mathematical transformations. Then, the relaxation modulus results were fitted to the Generalized Maxwell Model, which is a common model used to represent the viscoelastic properties of asphalt mixtures, and Prony series parameters were obtained. The results showed that the addition of capsule reduced the permanent deformation strength of the asphalt mixture. In addition, the curve fitting processes were successfully performed and the desired parameters were obtained with high accuracy.Öğe Predicting The Complex Modulus of Magnetic Activated Carbon Modified Bitumen Using Artificial Neural Networks(Duzce University, 2021) Özdemir, Ahmet Münir; Yılmaz, Bahadır; Tanbay, Nurten AkgünIn this study, the rheological properties of the bitumen modified with Magnetic Activated Carbon (MAC) were investigated and the results were predicted with artificial neural networks. Within the scope of the study, modified bitumens were obtained by adding 5%, 10% and 15% MAC to the B160/220 penetration grade bituminous binder. Then, a frequency sweep test at ten different frequencies (0.01-10Hz) and four different temperatures (40 °, 50 °, 60 °, 70 ° C) was carried out on original and modified bitumens with the Dynamic Shear Rheometer (DSR) device. The results showed that the addition of magnetic activated carbon improves the elastic properties of the binder by increasing the complex modulus and decreasing the phase angle values. Then, complex modulus and phase angle values, which vary depending on the frequency, addition content and temperature value, were predicted by artificial neural networks. The results showed that complex modulus and phase angle values of the bitumen can be obtained with very high accuracy and low error with artificial neural networks.Öğe Prediction of Rheological Parameters of Asphalt Binders with Artificial Neural Networks(ISRES Publishing, 2021) Özdemir, Ahmet Münir; Yalçın, Erkut; Yılmaz, MehmetRecycling of industrial, agricultural etc. wastes is economically and environmentally important. In recent years, researchers was focused on the using wastes in structural materials. In this study, modified asphalt binders were obtained by adding 7 different ratios waste engine oil (2%, 4%, 6%, 8%, 10%, 12% and 14%), which released as a result of routine maintenance of automobiles, to the pure asphalt binder. Then, Dynamic Shear Rheometer (DSR) experiments were applied on pure and modified asphalt binders. The rheological properties of asphalt binders at different temperatures and frequencies (loading rates) were evaluated by performing the DSR Test at 4 different temperatures (40°C, 50°C, 60°C and 70°C) and 10 different frequencies (0.01-10Hz). Then, the obtained complex shear modulus and phase angle values were estimated with Artificial Neural Networks. The results showed that the addition of 2% waste mineral (engine) oil improved the elastic properties of the asphalt binder by increasing the complex shear modulus and decreasing the phase angle values. In addition, it was concluded that the rheological parameters of asphalt binders can be successfully obtained with Artificial Neural Networks, by estimating the results with low error rate and high accuracy.Öğe Rheological Analysis of The Aging Behavior of Short-Term Aged Pure And SBS Modified Asphalt Binders(2025) Özdemir, Ahmet MünirFlexible pavements consist of a bituminous binder and certain graded aggregate. The performance of the bitumen determines the overall pavement performance. Bitumen undergoes short-term aging from production to application, accounting for most of its total aging during service life. This study rheologically investigates the short-term aging behavior of 70/100 pure bitumen and SBS-modified bitumen. Frequency Sweep test was performed on bitumen samples with Dynamic Shear Rheometer (DSR) device at different frequency (0.01-10 Hz) and temperature (40, 50, 60, 70°C) ranges. The complex modulus and complex viscosity master curves of the binders were obtained by processing the experimental data and the curves were subjected to rheological model analysis. The study showed that SBS modification enhanced aging resistance by preserving elastic properties. Moreover, the master curves were applied to rheological models with high accuracy.
