Researching On Evaluation Method And Index Of Segregation In AC-13 Coarse Aggregate

Asphalt pavement has become the primary type of pavement structure for highway in our country. The segregation of asphalt mixture is one of the main reasons for the damage in the early stage of the asphalt pavement. In recent years, many research organizations at home and aboard have explored extensively research on the segregation of asphalt mixture, but these researches were mainly aim at the asphalt pavement which is finished, very little was aim at the segreagation during the course of gradation design. The aggregate segregation of asphalt mixture on the one hand, because of improper construction; on the other hand, because of improper grading design. Therefore, the deeply research on the segregation in the course of gradation design, establishes suitable evaluation index and method, which has important significance to diminishing mixture segregation and raising the performance of asphalt pavement.In view of the AC-13 asphalt mixture's coarse aggregate, used the graduation vibration segregation experiment to obtain the optimal proportion between every grade of material, which was not easy to segregate. Used the SPSS statistic software to analyzed the relation between grade-deviation and content of every grade material, established the corresponding model, and analyzed the influence that every grade material to aggregate segregation.The uniformity can character the uniformity degree of aggregate pellet group. In view of the AC-13 asphalt mixture's coarse aggregate, studied the aggregate uniformity under different combination proportion. Used the SPSS statistic software to analyzed the relation between uniformity and content of every grade material, established the corresponding model, and analyzed the influence that every grade material to aggregate segregation.Through the gradation optimization design, obtained the gradation scope of AC-13 asphalt mixture, which is not easy to segregate. Chosen three grading curves which is in the determined gradation scope to carry on Marshall test, high temperature stability test and water stability test, examined the pavement performance though these tests.Through anglicizing the grade-deviation and uniformity, proposed the method and index for discriminating the segregation of coarse aggregate, which is used in the asphalt mixture grading of aggregate design.