Study On Regeneration Performance Of Asphalt Mixture In Cold Region

Asphalt pavement is widely applied to roads in China,especially on expressways,because of its excellent driving performance.Under the action of rolling,lighting and freeze-thaw cycles,transverse and longitudinal cracks,pits,boiling and other diseases will occur,which will affect the regular use of pavement.Every year,a large number of waste asphalt mixtures caused by maintenance and milling are not only wasted resources but also polluted the environment if they are not processed in time.At present,the more effective regeneration method is to regenerate the aging asphalt mixture by adding regenerative agent.The ratio of the regenerated old material is more than 50%,and some even reached 70%,but the aging resistance and fatigue resistance of the recycled materials are all attenuated,and the regenerated asphalt mixture is regenerated by the method of non regenerative agent,and the 90~#base of Panjin is selected.asphalt and aggregate for the aging of asphalt mixture regeneration.In view of the above considerations,the paper separates the asphalt and aggregate from the aging asphalt mixture by extracting and distilling the asphalt and aggregate in the aging asphalt mixture for the local service period of 10 years for the local service period of the Jilin provincial highway administration,and determines the penetration,softening point,ductility and rotational viscosity of the asphalt mixture,and the aggregate gradation,crushing value and the wear value of Los angeles,through the above tests.The asphalt aging degree and the mechanical properties of the aggregate in the old material are determined.According to the results obtained and the asphalt mixture of the target gradation,the mixture ratio of various materials is determined.The test pieces of Marshall test pieces,rutting plates and trabeculae bending are made according to different mix ratios,and the test data obtained by Marshall stability test,immersion Marshall stability test,rutting test,splitting test,freeze-thaw splitting test and trabecular bending test are obtained to determine the best old asphalt mixture and the new asphalt and new aggregate after re mixing.The performance change of recycled asphalt mixture with large mix proportion and old material blending ratio is also discussed.The test results show that the mixing ratio of AC-16 and AC-20 recycled asphalt mixture is kept within 27.9%and 28.6%respectively.With the increase of the mixing ratio of the old material,the low temperature stability of the asphalt mixture in the cold region is gradually reduced,but the basic road performance can meet the requirements of the rules and meet the regeneration conditions.The maximum Rap of this paper is 30.6%by fitting the bending strain and Rap curve of bending test.