Analysis And Evaluation Of Performance Index Of Asphalt Based On Hainan Climate

Asphalt pavement long-term exposure to the natural environment. In addition to the vehicle loads, it always withstands periodic influences of all kinds of cyclical changes in natural factors. Hainan province belongs to low-latitude regions, so it has its unique climatic characteristics. Therefore, based on the comprehensive survey of regional meteorological data in Hainan, one systematic research has been done on the influence of unique nature conditions on asphalt pavement in Hainan when referring to the U.S. SHRP research program. Further, it is taken a road-performance evaluation of SK-70 asphalt selected by the project.Firstly, after collecting the meteorological data of each region over the past thirty years in Hainan, and calculating the design temperature of high-low temperature by the relevant formula of U.S. SHRP program, it is carried on the temperature partition for asphalt road performance in Hainan area.Secondly, according to measured meteorological data and the temperature data collectted from different depths of asphalt pavement layer, it is discussed the major factors impacting on asphalt pavement temperature field using gray relation theory,and established the prediction formula of high-low design temperature and the temperature changing with the depth in Haikou using the origine software.Then,the comparative analysis was carried out between the regression formula and the fomula in the SHRP program.Thirdly, according to the basic principles of meteorology and heat transfer, it is analyzed the transient problem of asphalt pavement in Hainan detailly by ANSYS on the basis of measured data. Meanwhile,the comparative analysis is carried out between the measured temperature data and the numerical result tested on asphalt pavement in Hainan,which has verified the reasonableness and accuracy of the finite element model in this paper.Fourthly, according to the meteorology data in Hainan, test road structure scheme of G225 Haiyu west-line and the measured thermal parameters of asphalt pavement materials, it is established the finite element model to analyze the influence of the thermal conductivity variation of surface layer and the variation of base thickness on the temperature distribution in the internal asphalt pavement structure repectively. Then,the three-factor and three-level orthogonal test are used to discuss the scheme of structure and material impacting on the temperature field of asphalt pavement.Finally, according to the asphalt performance evaluation index determined by the climate in Hainan, it is carried on the routine test of original asphalt for the selected SK-70# asphalt,as well as the routine performance index(penetration, softening point, ductility and rotary viscometer) test and the SHRP high temperature performance index test for the aged asphalt residue in different degrees(concluding short-term aging and long-term aging).Then, it is valmade an evaluation of the high temperature properties and aging properties for SK-70 asphalt, combined with the DSC test.