Development Of High PG Grade Modified Asphalt And Study On Properties Of Mixture In Guangdong Province

Due to the high temperature and heavy rain all year round in Guangdong Province,and the continuous effect of heavy load traffic,the asphalt pavement appears serious rut disease soon after the opening of traffic,which affects the driving comfort and safety of the road.At present,SBS modified asphalt is the most widely used rutting prevention and control measure in the local area.However,it is found in the use process that it has been difficult to meet the performance requirements of high-temperature rutting resistance in some high-temperature and heavy-duty traffic areas.Therefore,in view of the high temperature,rainy and heavy load traffic environment in Guangdong,it is urgent to develop a high PG grade modified asphalt which can effectively improve the high temperature rutting resistance performance,so as to improve the service quality and service life of the asphalt pavement in Guangdong.In view of this,based on Meida expressway project,this paper systematically carried out the research and development of high PG grade modified asphalt and mixture performance.In this paper,firstly,the climate environment and traffic load conditions in Guangdong are investigated,and based on the local typical climate conditions,traffic conditions and measured pavement structure temperature and other factors,the recommended PG grade of asphalt in each region is established.Secondly,according to the PG grade of asphalt recommended by Guangdong region,the grade standard of high-grade PG modified asphalt is determined,and the high-grade PG modified asphalt is prepared and studied.According to the influence of the content of modifier,processing temperature,processing time,reaction rate and other factors on the conventional index performance,the key preparation parameters are determined.Based on the dynamic shear rheological test,the high temperature and fatigue resistance are studied.Based on the bending rheological test,the low temperature crack resistance is studied.The selected parameters are carried out Validation and optimization.Furthermore,on the basis of the above research results,the design and road performance of high PG modified asphalt mixture are studied in depth.Based on the rut test,Kentucky water immersion dispersion test and four point bending fatigue test,the high temperature stability,water stability and fatigue performance are studied respectively.Finally,based on the Meida high-speed test section,the key technologies for the development of high PG modified asphalt and the construction of mixture performance in Guangdong are proposed.At the same time,the economic benefits of high PG modified asphalt pavement are analyzed.In a word,this study can provide reference for improving the high-temperature rutting resistance of the asphalt pavement in Guangdong Province,and it has important practical significance for improving the service level and service life of the asphalt pavement in Guangdong and even the whole country.