Microstructure Analysis Of Dry SBS Modified Asphalt And Research Its Mixture Road Application Performance

In order to improve the performance of the pavement,SBS modifier is mainly used to modify the asphalt at home and abroad.At present,there are many defects exposed in the domestic wet product modified asphalt.The basic reason is that the SBS modifier is wet,that is,the asphalt is mixed in advance and then enters the mixing plant,which leads to the difficulty of process control and quality supervision,and brings a series of economic and environmental problems For this reason,dry process modification came into being.Because the dry process modification has not been widely used and the relevant research is not sufficient,this paper studies the dry process modification technology and analyzes its feasibility and advantages.The main research contents and conclusions are as follows:This paper describes the preparation process of sbs-t and SBS modified asphalt by wet method,analyzes the fluorescence micrograph of sbs-t modified asphalt under different dosage and different shear time,and compares the dispersion process of sbs-t modified asphalt and SBS modified asphalt within 45 min shear time by fluorescence micrograph.The results show that the network structure of sbs-t modified asphalt is better in the range of 4.5% to 6% of modifier content,and the dispersion effect of SBS modified asphalt has been achieved when the shear time is about 5min.The penetration,softening point,ductility and viscosity of the modified asphalt are similar to those of wet modified asphalt.The fluorescence micrograph of the modified asphalt was quantified,and the relationship between sbs-t area ratio and SBS swelling ratio and shear time was given.At high temperature,the area of modified asphalt increases with the time of temperature load,and the area shrinkage of sbs-t modified asphalt is equivalent to that of SBS modified asphalt;at low temperature,the area of modified asphalt decreases with the time of temperature load,and the area shrinkage of sbs-t modified asphalt is smaller than that of SBS modified asphalt.Through the pavement performance test,the high temperature performance,water stability and low temperature performance indexes of sbs-t dry mixing time of only 25 s are obtained,which can meet the requirements of specifications and road performance,and are similar to the performance of SBS modified asphalt and mixture.In this paper,the dry sbs-t modification method with easy quality control is studied,and the best process parameters and the performance of modified asphalt and mixture are defined.The dry sbs-t modifier greatly shortens the mixing time due to its obvious advantage of melting rate,and in the field construction,the dry sbs-t modifier technology omits the intermediate steps of preparing modified asphalt,so it has a significant advantage in economy and environmental protection compared with the wet sbs-t modifier.When the dry sbs-t modification technology is used in the actual project,the recommended amount of modifier is 4.5% to 6%,and the dry mixing time is 25 s.The research of this paper can provide reference and guidance for the further promotion of the dry sbs-t modified asphalt.