Investigation of Bitumen Modified Using High-Density Polyethylene Pyrolysis Oil

There has been an ever-increasing trend of plastic waste generation in recent years due to commercial and industrial development worldwide. Different studies were done on using plastic waste in the bitumen. High-density polyethylene (HDPE) waste is one of the major components of plastic waste. This study investigates the characteristics of bitumen modified with HDPE pyrolysis oil. Base bitumen is modified using 1, 2, and 3% HDPE pyrolysis oil. Properties such as softening point, viscosity, penetration, and Multiple Stress Creep and Recovery (MSCR) tests were investigated to check the behavior of modified bitumen. The mixing and compaction temperature of the base and modified bitumen is calculated using the viscosity-temperature relationship. It was found that penetration value increases as modifier content increases, which means modified bitumen improves cracking resistance. The softening point of modified bitumen is improved except for 3% HDPE pyrolysis oil modified bitumen. Modified bitumen decreases the viscosity of the base binder with increased pyrolysis oil content. Adding HDPE pyrolysis oil decreases mixing and compaction temperature concerning the base binder, which reduces energy consumption during the construction of flexible pavement. The addition of 1% HDPE pyrolysis oil enhances binders’ rutting resistance and is suitable for higher traffic loading conditions compared to base bitumen.