Research On The Low-temperature Anti-cracking Performance Of Asphalt Mixture Under Freezing Rain And Ice-snow Extreme Climate

In 2008, most area of southern China had suffered the extreme climate disaster such as freezing rain and snow-ice. At that time, asphalt pavement was damaged by disadvantage factors such as freezing rain, ice-snow and the deicing chemical etc. After the investigation, the crack is main disease of asphalt pavement; moreover crack will directly cause the other diseases of asphalt pavement. Therefore, in order to cope with the adverse effect of the extreme climate, reduce or eliminate low-temperature cracks, improve the quality of the road, through the deep study of asphalt mixtures on the low temperature cracking performance becomes very necessary.Asphalt, aggregate characteristics, grade and asphalt pavement performance are studied in this paper. One hand, used limestone as aggregate, the modified asphalt as binding, through they are compared with the CAM of R&D of Texas of the USA and the AC-13C which used commonly in China. According the grading theoretical to analyze the characteristics, the specimen of the modified asphalt of CAM and AC-13C are produced by the Marshall method; other hands, the performance of asphalt mixture are studied. Tests showed CAM addition to decreased anti-sliding performance of the other way with good performance. CAM has more impermeability and low temperature cracking performance than the AC-13C asphalt is significantly improved.Furthermore, the low temperature cracking performance of asphalt mixture performance is one of the key pavement performances on freezing rain and ice-snow extreme weather areas of asphalt pavement; it had disadvantage factors such as the low temperature, the low cycle, the deicing salinity. Currently the research and evaluation methods are also seldom. the paper based on a variety of unfavorable factors of asphalt mixture was 0℃bending creep tests and 0℃, -10℃and -20℃bending test studies, analyzes a variety of unfavorable factors of the asphalt mixture at low temperature cracking performance. The results showed that various unfavorable factors greatly reduced the low-temperature cracking of asphalt mixture performance, using the Grey Relation Analysis and two-way anova to compare the various negative factors degree of performance impaction the low-temperature cracking of asphalt mixture. In addition, CAM has superiority reply to freezing rain and ice-snow extreme weather Through this study, a comparative analysis of CAM and AC-13C, at the same time, a new asphalt mixture is provided and research directions to response to extreme climate.