Study On Performance Of SBS/APAO Composite Modified Asphalt And Mixture

As the most commonly used asphalt modifier,SBS not only has good high temperature rutting resistance and load resistance,but also has good low temperature crack resistance and fatigue resistance,but it also has some shortcomings,such as SBS and asphalt easy Defects such as segregation and delamination,poor storage stability,and relatively strict preparation technology have occurred.With the rapid development of modern transportation,traffic axle load,large flow,fast driving speed,and frequent occurrence of extreme weather,resulting in a single modified asphalt It is already difficult to meet the status quo.The APAO modified asphalt has good high temperature performance,and the preparation process is simple.It is easy to integrate with the asphalt and is not easy to separate.In addition,it can also be well mixed with PE,SBS,styrene-butadiene natural rubber,etc.to improve its Performance,but APAO modified asphalt has the disadvantages of higher viscosity and general low temperature performance.Based on the characteristics of the two modifiers and the good miscibility of APAO and SBS,this paper proposes SBS/APAO composite modified asphalt.On the basis of summarizing the research of other composite modified asphalt at home and abroad,the performance of SBS/APAO composite modified asphalt and the performance of composite modified asphalt mixture were studied.This paper first studies the process parameters such as shear speed,shear time and shear temperature of the SBS/APAO composite modified asphalt.The optimal processing technology obtained through orthogonal test is that the shear rate is 7000 r /min and the shear temperature is 170℃,shear time 60 min.Then 10 different types of APAO and different APAO dosages(0%,4%,8%)and SBS were compound modified to study the effect of APAO dosage on the performance of SBS/APAO composite modified asphalt,using BP neural network analysis APAO parameters affect APAO’s three major indicators.And the high-low temperature performance,temperature sensitivity,rheological properties,viscosity and anti-aging properties of SBS/APAO composite modified asphalt were studied.Studies have shown that adding APAO to SBS modified asphalt significantly improves the high temperature performance of asphalt and no significant improvement at low temperature.APAO improves the compatibility of SBS modified asphalt.At the same time,APAO improves the rutting resistance of SBS modified asphalt.SBS/APAO composite modified asphalt has good high-temperature rutting resistance,and the temperature sensitivity and anti-aging properties of SBS/APAO composite modified asphalt are significantly better than APAO Asphalt and SBS modified asphalt,APAO improves the temperature sensitivity and anti-aging properties of SBS modified asphalt.Finally,two types of SBS/APAO composite modified asphalt prepared by ten different types of APAO with the best performance were selected,and then the performance of the mixture was studied on matrix asphalt,SBS modified asphalt,and SBS/APAO composite modified asphalt.Through rutting test,low temperature trabecular test and freeze-thaw splitting test,the high temperature rutting resistance,low temperature crack resistance and water stability of different asphalt mixtures were studied.The results show that SBS/APAO composite modified asphalt mixture has good high-temperature rutting resistance and low-temperature crack resistance,but the content of APAO should not be too high.The 4% APAO SBS/APAO composite modified asphalt is better than 8%,and the freeze-thaw splitting strength of SBS/APAO composite modified asphalt is higher than that of SBS modified asphalt.The addition of APAO can improve the water stability of SBS modified asphalt.