Study On High Viscosity Composite Modified Rubber Asphalt And Performance Evaluation Of Its Mixture

High viscosity composite modified rubber asphalt(HVAR)can improve the overall adhesion and durability of asphalt mixture.Based on the technology of modified asphalt with waste tire rubber powder,this paper studies various technical indexes and performance parameters of three kinds of high viscosity modified rubber asphalt,as well as the mix proportion design,road performance,site construction process and quality control of three kinds of HVAR mixture,respectively,by adopting the composite modification method,and obtains the following conclusions:Based on the technology of modified asphalt with waste tire rubber powder and the principle of composite modification,three kinds of HVAR products were developed.The performance evaluation indexes such as 180? viscosity,60?viscosity,softening point,5? low temperature ductility and 25? elastic recovery were tested and analyzed.It was proposed that the technical standard of HVAR 60?dynamic viscosity should be no less than 20000 pa.s.At the same time,for HVAR,ordinary rubber powder modified asphalt(AR),SBS Three kinds of modified asphalt,such as modified asphalt,were tested and compared at 25?;BBR(bending beam rheometer)was used to test and compare the low-temperature performance of PG performance classification.Its performance indexes meet the technical requirements of high viscosity asphalt,with the characteristics of high viscosity,high softening point,high elastic recovery and high bonding performance.The low-temperature creep performance is equivalent to SBS,and the high-temperature and normal temperature creep performance is excellent SBS modified asphalt and AR asphalt.Based on the three kinds of developed HVAR,the mix proportion design,road performance test and production process of ac-10c dense graded asphalt mixture were studied.The Marshall test method is used to design the target mix proportion of asphalt mixture and obtain the best asphalt aggregate ratio(5.2%,5.7%,5.2%)of three kinds of HVAR mixture.Aiming at the water damage resistance,high temperature stability and low temperature crack resistance of asphalt mixture,the immersion Marshall test,freeze-thaw splitting test,rutting test and low temperature bending test of small beam are carried out to check and analyze.According to the test results,the Marshall technical index requirements and performance inspection index requirements of the mixture are determined.In the end,three kinds of Hvar are studied by selecting the second-class highway overhaul project of Liaoyang section of Shenyang Ring Road(S106),laying the 3.1km Hvar pavement test road and carrying out on-site tracking detection The production and mixing technology,paving and rolling technology,quality control and test and detection methods of the mixture are used for dense graded asphalt mixture.The high-temperature rutting resistance is significantly improved,the water damage resistance is better improved,and the low-temperature cracking resistance is improved to a certain extent.HVAR dense graded asphalt mixture is easy to have a certain amount of connected pores,so it is necessary to pay attention to rolling temperature and rolling workers Technology,to prevent the pavement from water permeability;in low temperature performance,it needs to be further improved.The research shows that Hvar can improve the technical performance of rubber asphalt and expand its application range,which is suitable for asphalt pavement with more strict requirements of heavy load traffic and water damage resistance.