Grey Correlation Analysis of Physical Properties and Evaluation Index of Graphene-Oxide-Modified Asphalt

The purpose of this study is to analyze the behavior of the performance index of graphene-oxide-modified asphalt. The deviation problem caused by determining graphene oxide content by single performance or several independent properties is also investigated. By testing the physical properties of graphene-oxide-modified asphalt with different admixtures (0%, 0.5%, 1.0%, 1.5%, 2.0% by mass) in terms of viscosity, penetration, softening point, ductility, rheology, etc., it is concluded that the addition of graphene oxide could improve the individual properties of the matrix asphalt by 3% to 250%. Moreover, the grey correlation analysis method is used to calculate and analyze the correlation between the performance of graphene-oxide-modified asphalt and the content of graphene oxide. The latter has the most significant effect on the softening point, the penetration, and the 135 °C Brookfield viscosity of modified asphalt. The content of graphene oxide in graphene-oxide-modified asphalt is calculated based on the above three performance indexes, and an estimation error of less than 0.15% is observed. This proves that the new determination method is reasonable. Finally, by combining the macroscopic properties and the multi-factor statistical analysis, a reference basis is provided for the quality control of the graphene-oxide-modified asphalt.