Characteristics performance of adding coconut shell bio-oil to petroleum asphalt

Currently, there is considerable research on modified asphalt using bio-oil prepared by fast pyrolysis and hydrothermal liquefaction methods, but research on modified asphalt using bio-oil prepared by extraction method is scarce. In order to investigate the rationality and applicability of bio-oil produced by extraction method as a modifier added to petroleum asphalt, the coconut shell bio-oil modified asphalt was first prepared by blending the bio-oil at 2%, 3%, 4%, 5%, and 6% with petroleum asphalt. Their conventional performance was evaluated based on penetration, ductility, softening point and viscosity. Their rheological properties were obtained by dynamic shear rheometer, bending beam rheometer and multiple stress creep and recovery. The modification mechanism was analyzed by gel chromatography and Fourier transform infrared reflection. The results show that the bio-oil can significantly improve the low temperature performance and fatigue resistance of the asphalt, but it is not good for the high temperature performance and temperature-sensitive performance. The added bio-oil increases the content of light components and decreases the content of asphaltenes in the asphalt, and the modification of petroleum asphalt by the bio-oil is not only a physical mixing but also a chemical process. The bio-oil has good compatibility with the asphalt binder.