Nanometer Zinc Oxide Modified Asphalt And Its Anti-aging Properties Research

For the present situation about the various diseases cause of the asphalt aging in the road usein gprocess, the theory that nano-ZnO as modifier to improve the anti-aging of the road asphalt is raised. The content of nano ZnO in the nano ZnO modified asphalt was designed,and a series of test experiments of the asphalt and nano ZnO modified asphalt were carried out, mainly including three index of performance test, dynamic shear rheological property testing(DSR), UV absorption test and segregation test, which analyzed the change of the performance and the mechanism of its modification about the modified asphalt. The results showed that, after adding nano ZnO, three properties of asphalt were improved in different degree, with a performance of decreased penetration, softening point rise and increased ductility; the ability of resisting the stress and strain was enhanced, and the elastic recovery showed when the temperature increased; the ultraviolet absorption intensity increased significantly, and it was several times of the absorption strength of matrix asphalt. Nano ZnO was compatible with asphalt, and the optimum content of nano ZnO was 3%. The Marshall stability test and the water immersion Marshall test of asphalt mixture was conducted,reflecting the improving effect of nano ZnO on the high temperature stability and water stability of asphalt mixture.The matrix asphalt and nano ZnO modified asphalt thin-film oven aging(TFOT) and indoor accelerated ultraviolet aging(UV) test, combined with the three major performance index test concluded that the nano ZnO could improve the anti-aging performance of asphalt,especially that the anti UV aging effect was obvious.Through the base asphalt and modified asphalt UV aging before and after dynamic shear rheological properties and infrared spectrum test, an analysis was made of the effect of nano ZnO on the rheological properties of asphalt and functional groups, to explore the modified asphalt aging mechanism and nano ZnO in asphalt aging mechanism in the process.The results showed that nano ZnO made asphalt showed a certain viscosity reply in the aging process; Nano ZnO could effectively reduce the asphalt aging process of characteristic functional index incremental and slow down the process of asphalt aging.Finally, in order to improve homogeneously dispersing ability of the nano ZnO in asphalt,graphene oxide and nano ZnO oxidation graphene composite was prepared. SEM(scanning electron microscope analysis was in progress,and the segregationput about the composite material matrix asphalt was tested. Results showed that the graphene oxide was a large piece of overlay structure; nano ZnO could be uniformly dispersed in the graphene oxide sheets layer structure; composite material and asphalt compatibility was quite good, which can improve the dispersing ability of nano ZnO in modified asphalt.