Research On Mix Design And Pavement Performances For BRA And SBS Compound Modified Asphalt Mixture

SBS modified asphalt mixture is a kind of pavement material which is widely used in the field of road engineering.At the same time,the Buton Rock Asphalt(BRA)have been more and more applications as a pavement asphalt material with higher performance-price ratio.Therefore,the thesis selects AC-13 as the research object to carry out the research on mix design and pavement performance for BRA and SBS compound modified asphalt mixture,so as to provide a new material technology reference for new pavement materials.1)According to the regulations,the Buton Rock Asphalt,SBS modified asphalt,coarse aggregate,fine aggregate and powder were tested,which composition of BRA and SBS compound modified asphalt mixture(referred to as BSAC-13C).The results show that the raw materials are in line with the requirements of technical specifications.2)The thesis designed the mix ratios and mixture ratio test for the BSAC-13 C mix under 5 different kinds of BRA mixing amount from 0% to 5%.The results show that the optimal SBS asphalt aggregate ratio is 5.06%,4.74%,4.56%,4.40% and 4.35%,respectively.With the increase of BRA content,the SBS optimal asphalt aggregate ratio gradually reduced,and there is a good linear relationship.It shows that the BRA can efficiently replace the part of SBS modified asphalt.3)Based on the results of the mixture ratio design,pavement performance tests are carried out.The results show that the high temperature stability and water stability of asphalt mixtures can be significantly improved with BRA added,but the low temperature performance is reduced,the suitable mixing amount of BRA is 3% ~ 4%,and the maximum bending strain ratio of the mixture is by 3.65%~5.67% compared with the conventional SBS modified asphalt mixture AC-13 C.Water permeability coefficient and texture depth test data show that the test result s conform to the specification requirements.Therefore,the optimal mixing amount of BRA is 3%.4)Through the comparisons of BSAC-13 C with SBS modified asphalt mixture AC-13 C from material costs,additional costs of production,maintenance and repair costs and the social benefits,BSAC-13 C has more economical and a broad application prospect.In summery,the proposed application technology of compound modified asphalt mixture BSAC-13 C in the thesis is reasonably practicable.It can be provided the reference for the further application and promotion of BRA and SBS compound modified asphalt pavement.