Research on the effect of carbon black on the features of hot mix asphalt

In this thesis, the improvements made by carbon black (CB) as an additive in the performance of bitumen and hot mix asphalt (HMA) and its employability were analyzed by researching within the terms of Superpave binder specification and the mixture design.To this end, getting air temperatures of past twenty years in Elazığ, binder performance grade was determined as PG 64-22 according to SHRP method. Based on PG 64-22 main binding, modified binders were obtained by adding 5%, 10% and 15% SK to PG 58-28 (B 160/220) binder in order to get a modified binder on the level of this binder. The features of pure and modified binders were analyzed by dynamic shear rheometer (DSR), bending beam rheometer (BBR), rotational viscometer (RV) and thermogravimetric analysis (TGA) experiments. Afterwards, forming a design aggregate gradation for Elazığ, mixture samples were prepared with pure and SK-modified binders, and the effects of SK on the performance of bituminous hot mixtures with indirect tensile strength (ITS) and moisture susceptibility, indirect tensile stiffness modulus (ITSM) and creep stiffness experiments. As a result of DSR, BBR, RV and TGA experiments of binders, according to pure B 160/220 (PG 58-28) binder, it was observed that high-temperature performance grade of the binder increased with SK addition, and there were significant increases in viscosity value and degradation temperatures. In addition, it was found that the modified binder generally equal to application area performance level was obtained by 10% SK addition and this rate was effective in the rise of binder stiffness. As a result of mixture experiments, maximum increase in indirect tensile strength rate was obtained from modified mixtures with 10% SK, the mixture that could be accepted as equal to the mixture with main binding in terms of indirect tensile strength was obtained from modified mixtures with 10% SK and the mixture that could be accepted as equal to the mixture with main binders in terms of stiffness modulus was obtained from modified mixtures with 15% SK. It was observed that the mixture which could be accepted as equal to the mixture with main binder in terms of creep stiffness could be obtained from modified mixtures with 2% SK at 40oC and modified mixtures with 10% SK at 60oC.At the end of the study, it was found that binders hardened and temperature sensitivity decreased; the fatigue resistance, cohesion and durability of the mixtures prepared with these binders improved and their strength against permanent deformations and water effects increased.Keywords: Carbon black, Asphalt, Hot mix asphalt, Superpave method, Performance grade, Modified bitumen, Modified mixture.