Comparison of Natural Asphalt with Ordinary Asphalt in Chemical Properties and Road Performance

摘要

Natural asphalt with rich resources could greatly improve the rutting-resistance and high-temperature performance of ordinary asphalt in pavements. Chemical properties and components of the Xinjiang natural asphalt and Binzhou No 90 asphalt were compared in this paper to explain the modification mechanism mentioned above. Samples were separated by liquid-solid chromatogram. Atterwards, VPO, 13C and 1H nuclear magnetic resonance, IR analysis and ultimate analysis were carried out. Results showed that resinal index of natural asphalt is 4.54, while that of Binzhou No 90 asphalt is 1.50. Ultimate analysis results indicated that the content of heteroatom (sulfur, nitrogen and oxygen) of natural asphalt was higher than that of Binzhou No 90 asphalt. IR analysis data showed that adsorption peaks of 1714 cm-1 and 1601 cm-1-1456 cm-1 of natural asphalt were stronger than those of Binzhou No 90 asphalt, which represented the absorption of the functional group of C=O bonds and the telescopic vibration absorption of C=C double bonds respectively, indicating that the C= O functional group was richer and its aromatics was stronger. Results of molecular weight and average structural parameters indicated that the asphaltenes of natural asphalt is inclining to conglomeration.