| With the rapid development of social economy,the car ownership has increased dramatically,thus produced a large number of the scrap tires,which created the "black pollution".Production the scrap tires into rubber powder,that can be modified asphalt used in pavement,not only could process part of waste tires,but also can improve road performance.Simply adding rubber powder in asphalt,however,will produce a lot of problems,restricting the development of rubber asphalt,such as the production of high temperature of asphalt aging,construction performance and construction environment problems,durable performance,etc.SMA aggregate structure has excellent resistance to deformation capacity,anti-sliding noise reduction,prevent mist phenomenon,improve visibility,and prolong the service life of pavement and good crack resistance at low temperature.But now the market generally uses the SBS modified asphalt,greatly improving the road construction cost,thus to find a material can not only reduce costs but also improve the performance of road using substitute,is the requirement of market development.For this reason,the research adopts the HCG type pyrolysis of the scrap tire rubber powder to modify asphalt,being able to formulate the excellent performance of rubber powder asphalt mixture.It will promote this material and can guide the engineering application.The paper used the penetration,ductility,softening point,rotary viscometer as evaluation index research technical characteristics of the modified scrap tire rubber powder asphalt,compared with no cracking agent of the scrap tire rubber powder asphalt.The performance of the modified scrap tire rubber powder asphalt would be changed on the three factors by wet process.The three factors were the scrap tire rubber powder content,cracking agent dosage and pyrolysis time.Then the results of the best proportion of the modified the scrap tire rubber powder asphalt,used for SMA aggregate structure.The paper researched the modified scrap tire rubber powder asphalt mixture performance.In this paper,with No.70 asphalt adding 20% of the scrap tire rubber powder,4 ‰ of pyrolysis,cracking two hours,the modified scrap tire rubber powder asphalt was produced.The tests on the road performance research include high temperature stability,low temperature crack resistance,water stability,and the fatigue properties in the modified scrap tire rubber powder SMA asphalt mixture.The results show that the modified scrap tire rubber powder SMA-13 asphalt mixtures had more superior performance.Water stability performance was significantly improved.Fatigue performance and low temperature performance were slightly higher than that of without cracking agent of the modified scrap tire rubber powder SMA asphalt mixture.The modified scrap tire rubber powder SMA asphalt mixture is more suitable for engineering practice,its work-ability is better. |
