| As the development of transportation industry,the asphalt pavement disease phenomenon has occurred under the complicated,changeable natural condition and the driving load.In recent years,because of the good comprehensive mechanics performance,the modified asphalt is more and more widely used in the field of highway engineering construction,such as adding new type mineral filler modifying agent such as ash and montmorillonite or enhancers to improve the performance of the asphalt,especially the polymer modified asphalt,such as SBS(styrene butadiene styrene block copolymer)asphalt and rubber asphalt application in a certain extent,reduce the early disease.But for colder regions like the northeast,there is further room for improvement in the use of polymer modified asphalt to prevent ruts and cracks.Therefore,it is a technical approach to improve the low temperature performance of asphalt by seeking a variety of reinforcer composite modified asphalt.According to the research thought,this topic through a variety of strengthening agent is added in the asphalt mortar,such as ash,SBS and rubber powder to improve the performance of asphalt mortar,and use a variety of craft made from composite modified asphalt mixture.In this paper,the mixture of SBS modified asphalt mixture,rubber-SBS composite modified asphalt mixture and ash-SBS composite modified asphalt mixture were prepared.Then this subject adopts penetration,ductility and softening point test was carried out on the performance of asphalt mortar,and high temperature rutting test and low temperature tm bending test on asphalt mixture of road performance testing,to determine the best mix proportion of each strengthening agent.Finally,this subject adopts in compression test under different temperature conditions for all kinds of specimen deformation behavior of the system of research,to reveal the complex strengthening agent of compression deformation of the micro mechanism of modified asphalt mixture.Based on the basic performance test of asphalt binder and the performance test of asphalt mixture,and the evaluation of mechanical properties of asphalt mixture under static pressure,the following conclusions are drawn.(1)By the test analysis all kinds of high and low temperature performance of modified asphalt mortar,the project finds that when the ash mortar was 8%,rubber powder mixed with 22% and SBS adding amount was 2%,the composite modified asphalt rubber paste has better comprehensive performance.This kind of sample is for the summer rutting of the seasonal frozen zone in Jilin province,and the cracks in winter have a better preventive effect,which is more conducive to the prevention and treatment of rutting and anti-crack in the road.(2)According to the various mixing ratio and various of composite modified asphalt mixture gradation road performance test and analysis,this article can be found that the SMA-16 grading,ash mortar was 8%,rubber powder mixed with 22% and added to the amount of 2% of the SBS modified asphalt mixture has better high temperature performance,better water stability,and greater stability.(3)According to the compression test,we can see that at room temperature,the performance of compression of modified asphalt mixture which has ash and rubber powder is significantly higher than the modified asphalt mixture,the ash samples on the compression strength of ascension.Will add the ash to a certain extent,however,to destroy the SBS asphalt in the 3-D mesh structure,which reduces the SBS in the supporting role of asphalt mortar,so at low temperature,the SBS in compression performance of asphalt mixture mainly enhanced role.But in at lower temperature,the contraction of asphalt mortar is the main factors influencing the compression performance,and the existence of the ash particles can improve the contraction of asphalt mortar,so at 40 degrees below zero,the ash can significantly improve the compression performance of composite modified asphalt mixture. |
PDF Full Text Request