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In this study, temperature sensitivity and storage stability of polyethylene and calcium carnonate compound (PEC) modified bitumen were investigated. PEC was used at the rates of 3%, 6%, 9%, 12% and 15% by weight of bitumen. The characteristics of PEC additived binders were confronted with 4% styrene-butadiene-styrene (SBS) additived binder. Penetration, rotational viscometer and softening point experiments were applied to determine the temperature sensitivity of the binders. After the storage process, dynamic shear rheometry and softening point experiments were applied to the binders. Moreover, their performance/cost relations were determined with the help of the approximate costs of the binders. According to the test results; The binder containing 15% PEC stands out with its low temperature sensitivity It has been appeared that there was a important phase separation after storage with an additive content of more than 6% in PEC modified binders. When the performance and costs of the binders are evaluated together, it has been determined that the binder containing 6% PEC has similar performance with 4% SBS modification in terms of temperature sensitivity, storage stability and economy., Bu çalışmada, polietilen ve kalsiyum karnonat bileşiği (PEC) modifiyeli bitümünün sıcaklık duyarlılığı ve depolama stabilitesi incelenmiştir. PEC bitüm ağırlığınca %3, %6, %9, %12 ve %15 oranlarında kullanılmıştır. PEC modifiyeli bağlayıcıların özellikleri, %4 styrenebutadiene-styrene (SBS) modifiyeli bağlayıcı ile kıyaslanmıştır. Bağlayıcıların sıcaklık hassasiyetini belirlemek için penetrasyon, yumuşama noktası ve dönel viskozimetre deneyleri uygulanmıştır. Bağlayıcılara depolama sonrası yumuşama noktası ve dinamik kayma reometresi deneyleri uygulanmıştır. Ayrıca bağlayıcıların yaklaşık maliyetleri yardımıyla performans/maliyet ilişkisi belirlenmiştir. Deney sonuçlarına göre; %15 PEC içeren bağlayıcı düşük sıcaklık hassasiyeti ile ön plana çıkmıştır. PEC modifiyeli bağlayıcılarda %6’dan daha fazla katkı içeriğinde depolama sonrası önemli derecede faz ayrımı olduğu belirlenmiştir. Bağlayıcıların performans ve maliyetleri birlikte değerlendirildiğinde %6 PEC içeren bağlayıcının %4 SBS modifikasyonu ile sıcaklık hassasiyeti, depolama stabilitesi ve ekonomik bakımdan benzer performansa sahip olduğu tespit edilmiştir.

Using hard and polymer-modified binders in stone mastic asphalt mixtures reduces workability considerably. In this study, Sasobit (Sasolwax, Worthdamm, Hamburg) is used in bitumen to increase the workability and efficiency of styrene-butadiene-styrene (SBS)–modified binders. The properties of SBS-modified and Sasobit-modified binders and mixtures were evaluated for their rheological and mechanical performances using different experimental techniques such as rheological bitumen tests—i.e., dynamic shear rheometer (DSR), bending beam rheometer (BBR), and hot-mixture performance tests; i.e., dynamic creep, fatigue, and toughness index tests. Sasobit improves the effectiveness of SBS modification, especially at medium to high temperatures, although it is not as flexible as SBS at low temperatures. In some cases, SBS modification is more effective than Sasobit modification when used alone. However, a better performance is achieved when 3% SBS plus 3% Sasobit is used when the two modifiers are mixed in the same binder, especially in terms of fatigue performance.

Bu çalışmada iki farklı boyutta (No.40 elek üstü ve altı) öğütülmüş araç lastiği (CR) ve öğütülmüş araç lastiğinin pirolizinden elde edilen karbon siyahı bitüm modifikasyonunda 3 farklı oranda (%5, %10 ve %15) kullanılmıştır. Saf ve modifiye bağlayıcılar üzerinde penetrasyon, yumuşama noktası, viskozite ve dinamik kayma reometresi (DSR) deneyleri uygulanmıştır. Ayrıca bağlayıcıların sıcaklığa karşı hassasiyetinin göstergesi olan penetrasyon indeksi (PI) değerleri belirlenmiştir. Penetrasyon, yumuşama noktası ve viskozite deneyleri sonucunda bitüm modifikasyonunda kullanılan CR miktarı arttıkça penetrasyon değerlerinin düzenli olarak azaldığı, yumuşama noktası ve viskozite değerlerinin düzenli olarak arttığı belirlenmiştir. Bu durum CR kullanımının bitümün rijitliğini arttırdığını göstermektedir. CR boyutu değerlendirildiğinde malzeme boyutunun bu üç deney üzerinde önemli bir etkiye sahip olmadığı belirlenmiştir. PI değerlerinden saf bitümlü bağlayıcıya kıyasla No.40 elek altı %5 CR kullanılan modifiye bitüm dışındaki tüm modifiye bitümlerin sıcaklığa karşı hassasiyetinin daha az olduğu belirlenmiştir. DSR deneyleri sonucunda CR içeriği arttıkça bağlayıcıların tekerlek izine karşı dayanım parametrelerinin ve elastikiyetlerinin arttığı belirlenmiştir. Öğütülmüş CR’nin pirolize tabi tutulmasından elde edilen karbon siyahının bitüm modifikasyonunda kullanılması CR’nin etkinliğini azaltmış özellikle No.40 altı boyuttaki CR’nin karbon siyahı saf bitümün özelliklerini iyileştirme özelliği göstermemiştir. In this study, two different sizes (smaller and larger sizes of No.40 sieve) of crumb rubber (CR) and the carbon black, which was acquired as a result of the pyrolysis of crumb rubber, were employed in the bitumen modification with 3 different rates (5%, 10% and 15%). Penetration, softening point, rotational viscometer and dynamic shear rheometer (DSR) tests were carried out on both pure and modified binders. Additionally, penetration index (PI) values, which is an indicator of binders against thermal sensitivity, were determined. As a result of penetration, softening point and viscosity tests, it was observed that with the increase of CR used in the bitumen modification, the penetration values decreased, and softening points and viscosity values increased regularly. This condition indicates that the stiffness of the bitumen increases with CR utilization. In the evaluation of the sizes of CR, it was determined that the sizes of the materials had no considerable effect on these three tests. In the PI values, it was concluded that thermal sensitivities were lower compared to pure bitumen, except in the 5% CR with smaller sizes of No.40. As a result of the DSR test, it was concluded that with the increase of CR content, the parameters of binders in the resistance against rutting and their elasticity were increased. The utilization of carbon blacks, which obtained from the pyrolysis of CR, in the bitumen modification reduced the effectiveness of CR and especially the carbon black from smaller sizes of No.40 CR demonstrated no improvement in the properties of pure bitumen.

Demandfor sustainable pavements increases day by day in asphalt paving industry. WarmMix Asphalt (WMA) technology has begun to be an interesting topic forresearchers owing to sustainability and environmental issues. Within the scopeof this study, the effect of an organic WMA additive was evaluated in terms ofmixture characteristics and performance. The fundamental and rheologicalproperties of bitumen samples involving organic WMA additive were determined byconventional bitumen tests and dynamic shear rheometer (DSR). Mixtures modifiedwith organic WMA additives were produced according to Marshall mix designmethod and the optimum bitumen content of the samples were determined.Following the determination of optimum bitumen content, the effect of the organicWMA additive was investigated in terms of indirect tensile stiffness modulus,fatigue and creep behaviour. Hamburg wheel tracking device was also applied toevaluate the permanent deformation characteristics of WMA mixtures incomparison to Hot Mix Asphalt (HMA) mixtures. The results appraised the effectof the organic WMA additive on rheological and performance characteristics ofbituminous mixtures.

Bu çalışmada çevresel zararları ve depolanması ciddi bir problem haline gelen mermer atıklarının, bitümlü sıcak karışım (BSK)’lardaki kullanılabilirliği ve nem hassasiyeti üzerindeki etkileri araştırılmıştır. Bu amaçla beyaz mermer, Elazığ vişne mermer atığı ve kalkerden oluşan agregalar, karışımda kaba, ince ve filler agrega olarak 9 farklı kombinasyonda kullanılmıştır. Gradasyonun tamamında mermer kullanılması durumunda optimum bitüm içeriğinde bir değişiklik olmamıştır. Bütün karışım tipleri Marshall stabilitesi bakımından standardın gerektirdiği minimum değeri fazlasıyla karşılamıştır. Filler olarak beyaz mermerin kullanılması koşullandırma sonrasında daha iyi stabilite değeri vermiştir. İndirek çekme mukavemeti değerleri kuru ve yaş numunelerde önemli farklılıklar göstermiştir. İndirek çekme mukavemeti oranlarına göre agregasının tamamı beyaz mermer ve kaba agrega olarak beyaz mermer dışındaki bütün mermerli karışımlar %70 değerinin üzerinde ve aynı zamanda kontrol karışımından daha iyi sonuçlar vermiştir., In this study the effects of waste marble the storage and environmental damage of which is being a serious problem on moisture sensitivity and the usability in hot mixture asphalt (HMA) was investigated. For this purpose the aggregates including white marble, Elazığ cherry and limestone were used as coarse, fine and filler in the mixture providing 9 different combination. The optimum bitumen content did not change in the case of using waste marble in the whole gradation. All the mixture types ensured exceedingly the minimum specification requirement. The use of white marble as filler gave more stability value than the others after conditioning. The indirect tensile strength values showed significant differences between the dry and wet specimens. All the mixtures except the mixtures containing white marble as whole gradation and as in only coarse aggregate, represented more than 70% retained tensile strength and also performed better results than the control mixture according to indirect tensile strength ratio.

Using a waste material such as crumb rubber (CR) obtained by waste tires has become an important issue in respect to sustainability. However, the CR modified mixture also requires high manufacture temperature as a polymer modified mixture. For this reason in this study, it is intended to produce a CR modified mixture with warm mix asphalt additives in the same mixture. Asphalt mixtures produced by pure, 10%CR, 10%CR+3% Sasobit and 10%CR+0.7% Evotherm were subjected to aging procedure in the laboratory and the field. The indirect tensile repeated tests were applied to aged and original specimens. It was concluded that the fatigue life of the mixtures increased significantly with the increase of aging time. CR+Sasobit modified mixture aged at the both field and laboratory gave the highest load cycle among the mixtures., {"references":["B. Şengöz, \"The effect of asphalt film thickness aging and moisture susceptibility of hot mix asphalt,\" Ph.D Thesis, ITU, 2003.","F. Yin, E. Arámbula-Mercado, A. Epps Martin, D. Newcomb, N. Tran, \"Long-term ageing of asphalt mixtures,\" Road Mater. Pav. Des. 18 (2017) 2–27.","J. Whiteoak, D. and Read, The Shell Bitumen Handbook, Thomas Telford Ltd, Londan, 2003.","F. Yin, A. Epps Martin, E. Arámbula-Mercado, D. Newcomb, \"Characterization of non-uniform field aging in asphalt pavements,\" Constr. Build. Mater. 153 (2017) 607–615.","J. C. Petersen, \"Chemical Composition of Asphalts as Related to Asphalt Durability; State of Art,\" Transp. Res. Rec. (1984) 13–30. http://onlinepubs.trb.org/Onlinepubs/trr/1984/999/999-004.pdf.","M. O. Hamzah, S. R. Omranian, A. Jamshidi, M. R. M. Hasan, \"Simulating Laboratory Short Term Aging to Suit Malaysian Field Conditions,\" World Acad. Sci. Eng. Technol. 72 (2012) 1499–1503.","H. R. Quintana, F. R. Lizcano, \"A review of asphalt and asphalt mixture aging,\" Ing. E Investig. 33 (2013) 5–12.","S. Wang, Q. Wang, S. Li, \"Thermooxidative aging mechanism of crumb-rubber-modified asphalt,\" J. Appl. Polym. Sci. 133 (2016) 43323(1-7). doi:10.1002/app.43323.","M. R. Mitchell, R. E. Link, F. Xiao, S. N. Amirkhanian, J. Shen, \"Effects of Various Long-Term Aging Procedures on the Rheological Properties of Laboratory Prepared Rubberized Asphalt Binders,\" J. Test. Eval. 37 (2009) 101706.\n[10]\tA. H. Ali, N. S. Mashaan, M. R. Karim, \"Investigations of Physical and Rheological Properties of Aged Rubberised Bitumen,\" Adv. Mater. Sci. Eng. 2013 (2013) 1–7.\n[11]\tA. Banerjee, A. de Fortier Smit, J. A. Prozzi, \"The effect of long-term aging on the rheology of warm mix asphalt binders,\" Fuel, 97 (2012) 603–611.\n[12]\tL. Francken, Bituminous Binders and Mixes: State of the Art and Interlaboratory Tests on Mechanical Behaviour and Mix Design, First Edit, E&FN Spon, 1998.\n[13]\tB. V. Kök, \"Investigation of a new mixing method in production of hot mix asphalt,\" Ph.D Thesis, Fırat University, 2007.\n[14]\tM. Fakhri, A. R. Ghanizadeh, H. Omrani, \"Comparison of Fatigue Resistance of HMA and WMA Mixtures Modified by SBS,\" Procedia - Soc. Behav. Sci. 104 (2013) 168–177."]}

Bu çalışmada, bitümmodifikasyonunda stiren-butadiyen-stiren (SBS), Amerika Gilsoniti (AG) ve İranGilsoniti (IG) kullanılmıştır. Uygulama bölgesi olarak Elazığ seçilmiş veElazığ’a uygun bağlayıcı elde edebilmek için %4 SBS, %11 AG ve %10 IGkullanılması gerektiği belirlenmiştir. Saf bitüm ve 3 farklı modifiye bitümkullanılarak bitümlü sıcak karışım (BSK) numuneleri hazırlanmış ve tasarımbitüm içerikleri belirlenmiştir. Çalışmada ayrıca filler olarak %2 oranındahidrate kireç kullanılmıştır. Tasarım bitüm içeriklerinde hazırlanan bitümlüsıcak karışım numuneleri üzerinde 25°C sıcaklıkta ve375 kPa gerilme seviyesinde indirekt çekme yorulma deneyi (IÇYD) uygulanmıştır.Elde edilen sonuçlardan bitüm modifikasyonunda SBS, AG ve IG kullanımınınkarışımların yorulma ömrünü arttırdığı belirlenmiştir. En yüksek yorulma ömrüdeğerlerine %11 AG modifiyeli bitümlerle hazırlanan karışımların sahip olduğubelirlenmiştir. Çatlak ilerleme oranı değerleri incelendiğinde bitüm katkımaddelerinin karışımların çatlak ilerleyişine karşı dayanımlarını arttırdığıbelirlenmiştir. Gilsonit kullanımının SBS’e göre çatlak ilerleyişine karşıdayanımı daha fazla arttırdığı tespit edilmiştir. Kireç kullanımının bitümkatkı kullanımı kadar etkin olmadığı belirlenmiştir.

The present study aimed to examine theresistance of pure hot mixes and those prepared with 4% of three differentpolymers two types of SBS (styrene-butadiene-styrene) and one type of EVA (ethylene-vinyl-acetate)against permanent deformation. Samples were prepared with application ofvibration so that they would have 4% void ratio using a roller compactor andwithout this application. The effect of vibration application during sample preparationon the wheel track formation was also assessed in the current study. Wheeltrack tests demonstrated that use of additives increased the resistance of hotmixes against wheel track formation. It was also determined that the mosteffective additive was EVA. Furthermore, it was determined that application ofvibration during sample preparation increased the resistance of specimensagainst permanent deformation.

In the present study, the effects ofstyrene-butadiene-styrene (SBS) and American gilsonite (AG) on the stiffnessand thermal sensitivity of bituminous binders were investigated in bitumenmodification. Şanlıurfa province was chosen as the application field. It wasdetermined that 18% AG and 5% SBS additives should be used separately to obtainthe adequate binder for Şanlıurfa province. It was also determined that 13% AGwith 2% SBS, 10% AG with 3% SBS and 6% AG with 4% SBS were required to obtainbinders with the same performance level. Penetration, softening point androtational viscometer tests were conducted on neat and modified bitumen todetermine the consistency of binders. Furthermore, thermal sensitivities ofbinders were determined from penetration index and penetration viscosity numbervalues. It was determined that all additives increased the consistency of thebinders, the most effective additive type and ratio was 18% AG on penetrationvalues, and all additives had similar effects on the softening point andviscosity values. In addition, it was determined that the temperaturesusceptibility was reduced with additive use and the most effectivecontribution came from 5% SBS.