Effect of Chemical Compositions on Temperature Susceptibility of Bitumens

The viscosity of five bitumens was measured at different temperatures and the viscosity-temperature relationship was developed to evaluate the temperature susceptibility of different bitumens. The generic fractions （i e, saturates, aromatics, resins and asphaltenes） of the bitumens were separated and tested by thin-layer chromatography with flame ionization detection （TLC-FID） and the effect of chemical compositions on temperature susceptibility of bitumens was analyzed using the linear regression method. The experimental results show that the four generic fractions play an inconsistent role in the temperature susceptibility of bitumens and the correlation degree of each fraction is somewhat different. The existence of aromatics and asphaltenes can lower the sensitivity to temperature changes whereas saturates and resins may have an adverse impact on the temperature susceptibility of bitumens. As for the correlation degrees, resins show the closest correlation with the temperature susceptibility of bitumens, then asphaltenes and aromatics, and the correlation between temperature susceptibility and saturates is relatively weak.