Study On The Mixture Design And Technical Characteristic Of Asphalt Mixture With The Buton Rock Asphalt

In recent years, Buton Rock Asphalt(BRA) widely used in road construction in our country because of its excllent pavement performance, economical price. However, at present, the technical performance specifications of BRA mixture has not been formed which limits its popularization and application. The paper studies on the doping process, gradation design method and design parameters of BRA mixture based on theory analysis and laboratory experiment.The paper studies on the physical state of BRA in the mixture and the effect of BRA on basis asphalt through the burning experiment, basket drainage experiment and settlement experiment. The results show that, BRA always maintains solid state in the construction process. BRA and basis asphalt is only physical blend and BRA produces settlement easily to result in the BRA segregation for BRA modified asphalt.So the “Wet” process is not suitable to BRA, the “Dry” process is recommended.Analysis four common gradation design methods and volume parameters of BRA mixture, the author proposed volume method of BRA mixture design. The BRA mixture designed by this method increases the optimum asphalt content, asphalt film thin and VMA compared with BRA mixture designed by dense gradation method.And the results show that this kind of mixture has more excellent pavement performance.Through a series of pavement performance tests, such as dynamic water scouring tests, Deformation-Strength tests, rutting tests, low temperature bending tests and aging tests, the pavement performances of BRA mixture designed by two king of method have been evaluated and compared with TLA mixture,CBL mixture, basis asphalt mixture.The results show that BRA can greatly improve performances of the basis asphalt, such as the high-temperature performance, low-temperature performance, moisture resistance and aging resistance.The author analyzes the effect of material parameters on mechanics properties of pavement by using BISAR3.0, recommend the reasonable scope of thickness, position and modulus of BRA structure layers and propose the BRA pavement structure which has economical and good performances.Through paving and performance testing of Bao-Han test road, the paper summarizes the construction technology of BRA modified asphalt concrete pavement. The economical analysis shows that BRA has favorable economic benefits.