Performance evaluation of bitumen modified with pyrolysis carbon black made from waste tyres

Two types of pyrolysis carbon blacks (PCBs) made from waste tyres were selected to modify road bitumens (SK70# and SK90#) via melt blending. The effects of the PCBs on physical properties, storage stability, rheological characteristics and performance grading (PG) of the bitumens were investigated. The thermal- and photo-oxidative aging of the PCB modified bitumens were evaluated by thin film oven test (TFOT), pressurized aging vessel (PAV) and natural aging (NA). Experimental results show that the high-temperature properties of the bitumen were obviously enhanced by both PCBs, leading to an improved resistance of bitumen to permanent deformation at high temperatures. The thermal- and photo-oxidative aging of bitumen were improved significantly by the PCBs. The pelleting pyrolysis carbon black (PCB-2) with bigger particle displayed more significant influence on bitumen performance than the normal pyrolysis carbon black (PCB-1) with relatively smaller grain size. The modified bitumen with appropriate dosage of PCBs can be used for road construction, which is of great significance for the improvement of pavement performance and recycling of waste tyres.