Characteristics And Application Technology Research Of Additived High Modulus Asphalt Mixtures

In recent years, with the combined effects of traffic growth, vehicle axle load heavier, traffic channeling and other factors, it is easy to produce pavement rutting. High modulus asphalt mixture made by doped high modulus directly, with its good high temperature performance and construction technology simple, easy to operate, has a broad application prospect.This paper chose two high modulus additives commonly used in the market to prepare high modulus asphalt mixture, and with characteristic of ordinary asphalt mixture were analyzed. Studied the principle of high modulus additives. Based on the test results of high temperature rutting test, low temperature bending test, freeze-thaw splitting test and fatigue test, the road performance of high modulus and ordinary asphalt mixture were evaluated. Study the mechanical properties of the additive type high modulus asphalt mixture and common asphalt mixture,by dynamic modulus and repeated load creep tests. By paving the physical works, construction control points of additive high modulus asphalt mixture were determined. Specific research conclusions are as follows:Extraction test results showed that the melting degree of high modulus additives in asphalt mixture was better. Scanning the recovered asphalt mastic by electron microscope, found that a small amount of large size additives particles remaining in the asphalt. DSR test results showed that the G’ showed a trend of increase gradually with the increase of high modulus dosage. This means adding high modulus can provide better high temperature deformation resistance.Using the empirical formula of G’, G ", G*, and the temperature,"lnG=AlnT", to analyze the influence of high modulus additives on asphalt temperature sensitivity, of which the absolute value of the slope A characterization asphalt binder temperature susceptibility. The test results showed that the absolute value of the slope A generally was decreased gradually along with high modulus additives content increased, with the increase of high modulus additive dosage, asphalt temperature sensitivity gradually reduce. It is beneficial to improve the strength of the asphalt mixture at high temperatureCompared with ordinary asphalt mixture high modulus asphalt mixture has better high temperature stability, water stability and fatigue resistance, but low temperature stability is closer.The test results show that the test temperature, frequency, and different materials have a significant impact on the dynamic modulus and phase angle of the asphalt mixture. The dynamic modulus of high modulus asphalt mixture in the case of15℃and10Hz can reach14000MPa above. FN get by repeated load creep test is2times the ordinary asphalt mixture, and a good correlation between the dynamic stability and FN is verified.Mechanics analysis results indicate that high modulus asphalt mixture should be used in middle course. Finally, by paving a test road, summed up the construction process of the additive high modulus asphalt mixture, analyzed the economic and social benefits of the additive high modulus asphalt mixture.