Restoration capacity of bio-oil to recycled asphalt and determination of optimum content
This study explores the potential of bio-oil in rejuvenating the performance of aged asphalt.A bio-oil with high rejuvenation capacity was chosen to determine the optimal dosage.Three types of bio-oil,namely veg-etable pitch,waste cooking oil,and industrial animal oil,were employed as rejuvenators to treat aged SBS modified asphalt.The impact of bio-oil type and dosage on the various properties of aged asphalt was evaluated through the measurement of the penetration,ductility,softening point,Brookfield viscosity of the bio-oil recy-cling asphalt,and thin film oven test.The results indicated that all three types of bio-oil possessed some recy-cling capability towards the fundamental performance and aging resistance of aged SBS modified asphalt.Waste cooking oil exhibited a stronger rejuvenation effect and offered higher social and economic benefits,followed by namely vegetable pitch and industrial animal oil.Waste cooking oil has been selected as the optimal recycled bio-oil,and a 4%content can completely restore the viscosity and high-temperature performance of aged SBS modi-fied asphalt,thus being determined as the optimal content.