Composite Modified Asphalt Of Coal Tar / SBS

Coal tar pitch(CTP),a product extracted from coal tar preparationsdistillation fractions,has lower price,higher adhesion and better anti-agingproperties compared with petroleum asphalt.Therefore,blending CTP withasphalt,which can improve the road performance,is one of the main topicsof high way industry. The best road performance can，t reach the best byusing only CTP. So it is necessary and meaningful to investigate modifiedasphalt by blending CTP and SBS.In this paper, CTP comes from Taiyuan chemical factory,SBS comesfrom Beijing Research Institute of Highway Ministry of Transport andpetroleum asphalt comes from shenghua refinery factory. The modifiedasphalt was made under different conditions in the special vessel.It isanalyzed for three main properties such as softening point,penetration andductility. Furthermore,thin film oven test was carried out for anti-agingproperties.The results show that different stirring method has been studied byblending different CTP%with asphalt.The result shows that the threemain properties of modified asphalt become more and more closer withthe increase of CTP ratio when compared physical stirring and shearstirring. While20%CTP added, the way of physical stirring performanceis better than shear stirring, which suggests the important effect of stirringway.Furthermore, SBS was used to improve the ductility in this paper.Theresults show that the best conditions are at20%CTP ratio for60~80mesh,and1.5%SBS ratio.The anti-aging test shows different CTPparticle size can influence the degree of aging properties and the optimalparticle size is60~80mesh finally,modified mechanism was investigatedby analyzing the toluene insoluble content of CTP under different meshwith penetration decrease.