Research On The Performance Of Asphalt Mixture Modified By Buton Rock Asphalt Composite With SBR

Among various modifiers,natural bitumen has been favored by road workers because of its good combination with matrix asphalt and rich reserves.As a geological resource,it is an organic matter produced by petroleum products in complex geological environment.Among them,Boudun rock asphalt modified asphalt has excellent high temperature performance and durability and the construction process is simple and the price is reasonable.However,it is brittle and crack resistance is poor at low temperature.In order to improve the low temperature performance of Bourdon rock asphalt(BRA)modified asphalt,SBR with different content and different dosages was added to BRA to improve the low temperature performance of Bourdon rock asphalt modified asphalt.And the resulting composite modified asphalt and mixtures were compared.In this paper,firstly,we will do a comparative analysis by the different content of SBR powder and SBR latex modified asphalt.At the same time,we can determine the optimal state and dosage of SBR in the composite modified asphalt which composited by BRA and SBR.Then make a design of mix proportion for the composite modified asphalt with BRA and SBR latex at optimal dosage.We can determine the optimum asphalt aggregate ratio depend on the design of mix proportion.Continuely,pavement performance of five kinds of mixture that comprise matrix asphalt,SBR modified asphalt,Buton rock asphalt(BRA)modified asphalt,SBS modified asphalt,composite modified asphalt is contrasted by high temperature performance,water resistance performance and low temperature cracking resistance.Finally,we will confirm the applicability and superiority of BRA and SBR latex composite modified asphalt by uniaxial compressive test and fatigue test at low temperature low frequency.The test results show that:1.Compared to the SBR powder,SBR latex has better improvements for low temperature performance,and high temperature performance of asphalt increased slightly.We suggest that the best physical status of is SBR latex and optimal dosage is 5%.2.The mixture of BRA modified asphalt,SBS modified asphalt,composite modified asphalt has better high temperature stability;Above of the three mixtures,they both show the same water stability and it is slightly better than the matrix asphalt mixture.Compared to SBS modified asphalt mixture,BRA and SBR latex composite modified asphalt mixture is not so good,but they don’t make much difference.So the SBR latex modified agent is added to the Buton rock asphalt modified asphalt can reach the same level low temperature resistance with SBS modified asphalt.3.Relatively speaking,BRA and SBR latex composite modified asphalt mixture has better compressive strength,while fatigue performance is slightly better than SBS modified asphalt mixture under low temperature and low frequency.