Rheological Properties Of TiO₂/ZnO-basalt Fiber Composite Modified Asphalt And Mixture Performance Research

As the asphalt pavement is comfortable,smooth,and low noise,it is widely used in high-grade pavement.However,most asphalt pavements suffers from early diseases such as low-temperature cracking,high-temperature rutting,and varying degrees of water erosion during service.In order to improve the high and low temperature performance and water stability of asphalt pavement,this article will incorporate nano-Ti O₂/Zn O and basalt fiber as modifiers into the asphalt to comprehensively improve its road performance.In this paper,nanometer material Ti O₂/Zn O-basalt fiber composite modified asphalt with different dosages was prepared.With the help of dynamic shear rheometer,bending beam rheometer and other test methods,the dynamic flow of composite modified asphalt binder before and after aging was studied Variable characteristics and low temperature creep characteristics.Infrared spectrometer and field emission scanning electron microscope（SEM）were used to analyze the chemical composition and microstructure of the composite modified asphalt,and explore the mechanism of the modifier.Through the four-point bending fatigue test and other road performance tests,the influence of the composite modifier on the road performance of the mixture was analyzed.Based on the basic test and Brinell viscosity test index,it is found that the viscosity of the composite modified asphalt is greater than that of basalt fiber modified asphalt（BF）and matrix asphalt,and the temperature-sensing performance is also better than that of fiber modified asphalt and matrix asphalt.The incorporation of composite modifier can significantly improve the high temperature stability and fatigue performance of asphalt.The low temperature performance of asphalt binder is weakened by fiber blending,and still meets the requirements of the specification;the appropriate amount of nano-material Ti O₂/Zn O modifier can improve the low temperature performance of BF modified asphalt.No new functional groups are produced after asphalt modification,and the modification mechanism is mainly physical modification.The cross-section of the composite modified asphalt is rough,and the nano-materials are more evenly distributed in the asphalt,which cooperates with the fiber to delay the propagation of internal micro-cracks.Based on the response surface method,the nanometer Ti O₂/Zn O dosage,the basalt fiber dosage and the whetstone ratio are used as the response input indicators,and the Marshall physical index is used as the response output index to determine the most of the whetstone ratio,the nanomaterial dosage and the basalt fiber dosage Good value.The AC-13C grade is selected.Under the best oil-stone ratio of the base asphalt,BF modified asphalt and composite modified asphalt and the best blending amount of modifier,it effectively improves its high-temperature rutting resistance,low-temperature crack resistance,water Stability and fatigue performance.