Research Of The Aging Characteristic And The Recycling Performance Of SBS Modified Asphalt

Lots of engineering projects shows that the old asphalt mixture recycling technology can benefit our society,economy and the environment.And this technology respond to the continuous development strategy well in our country.Because of the superior performance of SBS modified asphalt,it has been widely used in highway engineering in our country in recent years.As the increasing number of the soon-to-expire asphalt pavement,the aging characteristics of SBS modified asphalt and the performance of the recycled SBS modified asphalt became the important research topicFirstly,we studied the pavement performance indexes which will be influenced during the extraction test by blank calibration test.Used simulate aging test to simulate the different aging level asphalt,and tested their performance indexes.Regression analysis between the different pavement performance indexes and the aging time point out that the needle penetration is the most reliable and stable index in those aging evaluation indexes.With the needle penetration-time regression analysis curve,we can simulate the asphalt in RAP which can be used in recycling study without the influence of extraction test.Secondly,the recycling performance of SBS modified asphalt has been studied by comparing and analyzing pavement performance indexes of recycled asphalt which add the new asphalt or the rejuvenating agent only and add the new asphalt and the rejuvenating agent both.The result shows that add both rejuvenating agent and fresh asphalt can regenerate the old asphalt comprehensively,and there's a best scale of fresh asphalt and recycling agent to reach the excellent performance.It has a preeminent ratio to restore the pavement performance of SBS modified asphalt greatly in the complex regenerated way.