The Relationship Between The Performance Of Asphalt Based On AFM And Functional Groups

The effects of such factors as rain,sunshine and traffic load during the construction period and the use period of Asphalt Mixture Pavement,prone to aging,affect the service life of asphalt pavement,especially for OGFC-13 asphalt mixture pavement.In this project,analysis and quantitative characterization of micro properties(nano morphology,adhesion force,functional groups,etc.)of the different aging degree of base asphalt,SBS modified asphalt and asphalt extracted from OGFC-13 asphalt mixture,to exam its inner link and aging mechanism.At different aging degrees of base asphalt,SBS modified asphalt and asphalt extracted from OGFC-13 asphalt mixture,tests were conducted for atomic force microscope and infrared spectrum,quantitative characterization of asphalt morphology(quantity,average area,maximum area,wavelength,wave height map and Rq roughness of "bee-structure"),phase,adhesion,carbonyl index,sulfoxide group index and butadienyl index.At the same time,the aging mechanism of asphalt molecular weight was quantitatively analyzed.The results show that:(1)Asphalt "bee-structure" morphology consists of peaks and troughs,and the half peak width,peak wavelength(trough)height and area size of a single "bee-structure" increased to some extent after aging;(2)Aging influence the nano mechanical properties of asphalt,different micro regions of the asphalt surface may have different adhesion forces,and the "bee-structure" has the lowest adhesion force;(3)The content of the oxygen containing functional groups increased,and the degradation of the SBS modifier was induced by aging;(4)The powder of OGFC-13 asphalt mixture and lignin fibers in the vicinity of 1030cm-1 showed obvious characteristic peaks,and the wave number in the nearby 1700cm-1and 966cm-1showed no obvious characteristic peaks appear;(5)The changes of the chemical characteristics of the functional groups of asphalt has a good relationship with the changes of the micro morphology;(6)The proportion of large particle size of OGFC-13 asphalt mixture increased after aging,particle size of the small molecule ratio decreases,the proportion of large particle size and small particle size in asphalt has good relationship with the chemical properties of functional groups and microscopic morphology.