Research On Performance And Mechanism Of Waste Rubber Powder Modified Asphalts

According to the problem of the increasing traffic flow, heavy-load vehicles and over-loading trucks of the asphalt of high-grade highways especially of the express way in our country, using polymer to modify asphalt has been a valid method and a developing direction to mend the application performance of asphalt. And waste rubber powder modified asphalt has been popular used and deeply studied worldwide because of its abundance, cheapness, simple technics and extraordinary performance.At first, this paper summarized the theoretical researches ,the actual state of application and progresses of the polymer modified asphalt internal and external. Then based to Grey System theory, orthogonal design and some technical conditions, the right matrix asphalt, waste rubber powder and substance-supporting were selected to make compatible modified asphalt and complex modified asphalt by appropriate technics, besides, their performance indexes were measured. At last, based on the performance of the modified asphalt, the modern analysis technology was used to study the mix mechanism of the modified asphalt and the complex modified asphalt.Based on the comparison of the assessment method of polymer modified asphalt from both national and abroad, the research adopted the conventional testing methods to evaluate the modified asphalt, then the data were analyzed and compared. The result shows that the modified asphalt is better than the matrix asphalt in terms of the high-temperature stability, aging resistance and stability; And the complex modified asphalt is better than the modified asphalt in terms of ductibility, the low-temperature stability, aging resistance and stability.This paper used modern analysis technology to study the mix mechanism of the modified asphalt and the complex modified asphalt. They were Fluorescence optical microscopy, IR, DSC, and NMR. The analysis of Fluorescence optical microscopy concludes that particles of the waste rubber powder had become smaller and more well-proportioned because the oil in the substance-supporting was absorbed by the waste rubber powder; The analysis of IR concludes that the spectrograms of the modified asphalt are only the waste rubber powder and the matrix asphalt spectrogram, moreover, there's no chemic reaction between the substance-supporting and the waste rubber powder modified asphalt; The DSC spectrogram of the complex modified asphalt is flatter than the modified asphalt, and the modified asphalt is flatter than the...