Biochar effects on the performance of conventional and rubberized HMA

Biogenic carbon made from biomass waste (referred to as Biochar here) has shown to enhance rheological and mechanical properties of asphalt binder. This paper presents the results of using biochar as an additive in Hot Mix Asphalt (HMA). The Semi-Circular Bend (SCB) test and the Hamburg Wheel Tracking (HWT) test were selected to analyze the resistance to fracture and rutting, respectively. Also, the resistance to colour degradation of HMA was evaluated using the Xenon Arc Test. The SCB test results suggested that biochar's presence led to an increase of strain energy and subsequently higher resistance to fracture. HWT test results showed that biochar's presence reduced total permanent deformation after 20,000 cycles and subsequently enhanced resistance to rutting. As for the resistance to colour degradation, biochar's addition helped preserve colour and decrease the surface degradation of the asphalt mixture exposed to solar radiation compared to the control mixture.