Study On Aging Performance And Aging Mechanism Of ACM Modified Asphalts And Mixtures

To improve the road performance of asphalt and asphalt mixture after long-term aging,on the basis of the early study of the research team,we developed four kinds of Asphalt Comprehensive Modifiers(ACM),then focused on 26 kinds asphalts(4 kinds of ACM x 3 kinds of dosages x 2 kinds of asphalt)and aging performance of asphalt mixtures,and discussed the anti-aging mechanism of different asphalts.This study prepared theoretical foundation and scientific basis for the popularization and application of asphalt composite modifiers and further optimize the research,and had the vital significance and the certain theory reference value for engineering applications.The paper adopted RTFOT and continuously oven heated test to simulate the short-term aging and long-term aging,analysis and evaluate the aging performance and regulation by three conventional indicators and viscosity test of 26 kinds of asphalts,then discussed the modification mechanism and the anti-aging mechanism of ACM modified asphalt by fluorescence microscopy and IR analysis.At last,verify the aging performance of ACM modified asphalt mixtures before and after aging.Study showed that:(1)In terms of 70#asphalts,anti-aging performance of ACM4 modifier was best,followed by ACM2 and ACM3,ACM1 was the worst.Compared with 70#asphalt,the anti-aging performance of modified asphalts were better than 70#asphalts except ACM1 modified 70#asphalt,but worse than SBS asphalt.(2)In terms of comprehensive modified SBS asphalts,anti-aging performance of ACM2 modifier was best,followed by ACM4 and ACM],ACM3 was the worst.Compared with SBS asphalt,the anti-aging performance of modified asphalts were better than SBS asphalts except ACM1 modified 70#asphalt.(3)The more steady of microscopy of asphalt and the more intensive and uniform of modifier element,the better anti-aging performance the asphalts had.(4)Put forward the comprehensive aging index(CAI)which represent the aging degree of asphalt,establish the equation between CAI with carbonyl index CI and sulfoxide base index SI,the equation and IR analysis could be used to judge the anti-aging performance of different asphalt.