Research On The Performance Of Domestic Rock Asphalt And Its Mixture

The performance of asphalt and asphalt mixture has attracted more and more attention with the rapid development of our country highway transportation. Saving resources and reducing cost has been considered as the main factors when the materials were selected in the new road. Domestic natural asphalt has been more and more widely used because of its unique advantages and low cost. In view of excellent characteristics, the research of taking domestic natural asphalt as road asphalt modifier is particularly important.Domestic rock asphalt of qingchuan was taken as the research object. Then it was contrasted with the other asphalt, which are buton rock asphalt(BRA) and Trinidad lake asphalt(TLA).In order to study chemical composition, four component ratio and the modification mechanism, the microstructure of was analyzed. The research showed that in the qingchuan rock asphalt some silicate material were found, such as quartz(SiO2), calcite(CaCO3), plagioclase(NaAlSi3O8), illite and kaolinite. The content of asphaltenes and pectin was as high as 81.75% and 11.56%, which are significantly higher than base binder. And the modification to matrix asphalt belongs to the physical modification.China shipping 70 # asphalt was taken as the matrix asphalt to do the modified asphalt performance test study. The modification effects of different content qingchuan rock asphalt, BRA and TLA to matrix asphalt were studied through the penetration experiment, softening point test, ductility test, aging test and viscosity test. Meanwhile, the preparation technology for qingchuan rock asphalt was optimized by orthogonal test of the four factors three levels. The study showed that three kinds of natural asphalt made the matrix asphalt performances improved, which included high temperature performance, ability to resist deformation and temperature sensitivity. And the content of three asphalts was determined, qingchuan rock asphalt content is 5% ~ 10%, TLA and BRA content is 20% ~ 40%. Meanwhile, the orthogonal test results showed that the effect from shear time was the most significantly, followed by the shear temperature. The effect from development time and temperature was weakest, and both sorting was not necessarily.Based on the natural asphalt performance test results, three kinds of modified asphalt mixture performance were compared. It found that the road performance of three kinds of natural asphalt mixture were better than the matrix asphalt, and high temperature performance and water stability performance is obvious. Through the road performance test, the optimum content of the natural asphalt was determined respectively. Qingchuan rock asphalt is 7.5%, BRA asphalt is 30%, and the TLA lake asphalt is 35%.Finally, qingchuan rock asphalt was introduced in detail the construction technology. The benefit after using was analyzed contrast among matrix asphalt, three kinds of natural asphalt and SBS modified asphalt. Domestic qingchuan rock asphalt can obtain better economic, social and environmental benefits at a relatively low cost, which has obvious advantages in its development prospects.