Study On The Application Of Waste Tire Carbon Black Modified Asphalt

Along with the economic development,China produces a large number of waste tires every year.Pyrolysis is one of the most optimal ways to process waste tires.A more effective approach to recycle and make value-added use of waste tires largely is the pyrolytic carbon black being used for asphalt modification.In this paper,some performances of the asphalt modified with pyrolysis carbon black are improved significantly,such as the high temperature performance.In order to further perfect other properties,carbon black(CB),crumb rubber(CR),rubber and plastic alloy,SBS are used for composite asphalt modification.On the basis of the study on the complex modified asphalt and mixture,this paper puts forward a program that can make modified asphalt with excellent performance by means of being modified with recycled product out of waste tires,make up for the performance disadvantage of asphalt being modified with carbon black,crumb rubber or rubber and plastic alloy alone,achieve rational utilization of recycled product out waste tires,and reduce the production cost of modified asphalt.First,this study selects CB to modify asphalt,testing the penetration,softening point and low temperature ductility,and evaluating the modification effect.Upon the in-depth study of the rubber and plastic alloy/SBS compound modified asphalt with a alloy content variable and the CB/rubber and plastic alloy/SBS compound modified asphalt with a CB Content variable,this paper evaluates emphatically high-and-low temperature performance,anti-fatigue performance and operational performance from two different measurement systems which include the conventional properties(containing Penetration,ductility,softening point,TFOT and segregation)and the rheological properties(containing temperature sweep test,frequency sweep test,multiple stress creep recovery test,linear amplitude sweep,bending beam rheological test and Viscosity test).Then based on microstructure observation,it makes a tentative study of the corresponding Asphalt modification mechanism.This paper carries out the following corresponding asphalt mixture tests:rutting test,low-temperature bend test,Immersion Marshall Test and freeze-thaw splitting test and make a study of high temperature stability,low temperature crack resistance and water stability.Through the above study,these following conclusions are found.(1)CB has obvious stiffening effect on modified asphalt.It can improve the high temperature performance and has little influence on the low temperature performance;(2)Rubber and plastic alloy/SBS compound modified asphalt has more prominent high temperature performance,good low temperature performance in spite of low temperature ductility being reduced.(3)CB/rubber and plastic alloy/SBS compound modified asphalt has optimal high temperature performance,nice high temperature storage stability and elasticity,fatigue resistance being improved and low temperature performance being affected slightly.(4)CB makes modified asphalt mixture with high temperature rutting resistance being improved obviously,low temperature flexibility being improved appropriately and water stability being affected slightly.The compound modified asphalt with two kinds of modifier:rubber and plastic alloy and SBS can achieve the complementary advantages.It gives full play to the performance advantages of SBS high temperature and rubber and plastic alloy low temperature flexible.On the basis of rubber and plastic alloy/SBS compound modified asphalt,this study adds CB in the asphalt in order to further improve the performance of high temperature and anti-aging with low temperature flexibility and water stability performance being affected slightly.