Experimental Study On High And Low Temperature Performance Of Warm Crumb Rubber Modified Asphalt Mixtures Under Freeze-Thaw Cycle

People gradually realized the importance of environmental protection with the outstanding global environment problem and the sustainable development of economy and natural environment is a problem concerned on a global basis.The crumb rubber modified asphalt mixture provides a good solution to the handling of waste tires.But high mixing and construction temperature is required because of the high viscosity of crumb rubber modified asphalt,this makes a large amount of harmful gas produced in the course of producing the asphalt mixture which causing secondary pollution to the environment,meanwhile,maintaining the high temperature of the asphalt mixture will consume a lot of energy.Warm mix technique can solve the above problems effectively.So,the warm mix technology in the world has reached a high level of attention and rapid development in recent years.Wintertime sustaining over long periods of time and ice and snow is not easy to melt in China's Inner Mongolia region.And it has a great impact on the performance of the pavement.Therefore,snow melting is often done by spreading the deicing salt.While the asphalt pavement is in the alternate state of the freezing and thawing cycle,and the ice salt solution will also have an erosive effect on the pavement,which poses a severe test for the long-term performance of the asphalt pavement.The region at the same time the highest temperature can reach above 60 ?,the summer pavement rutting of asphalt pavement easily happened under the temperature,which has a serious impact on the driving comfort and driving safety of road.At the same time compared to the low temperature cracking,The high temperature rutting is more serious to the road.Therefore,in consideration of the central and western regions of Inner Mongolia high and low temperature performance of asphalt pavement when should pay attention to the following two points: ?1 Guaranteeing asphalt mixture has better rutting resistance at high temperature and give attention to both the low temperature cracking resistance of asphalt mixture;?2 Ensuring that the asphalt mixture has better anti-freeze and salt erosion ability.Article is mainly through the three-axis repeated loading creep test,the low temperature bending test and the bending creep test under the action of the freeze-thaw cycle and under the salt contamination with high and low temperature performance of warm mix rubber modified asphalt mixture are analyzed in view of this.Firstly,rubber powder modified asphalt mixture through Marshall design method of the mixture ratio is designed,and the optimum asphalt content of 5.45% is confirmed.Warm mix asphalt mixture of mixing and compaction temperature are 145? and 160?,respectively.Secondly,the high and low temperature performance of rubber powder modified asphalt mixture influence factors are analyzed under the action of the freeze-thaw cycle.The four types of asphalt respectively warm mix hybrid mesh rubber powder modified asphalt(WJH),hybrid mesh rubber powder modified asphalt(JH),warm mix 60 mesh rubber powder modified asphalt(WJ60),60 mesh rubber powder modified asphalt(J60)are selected.4 freeze-thaw cycles are selected.4 kinds of deicing salt concentration are selected.Research shows that: high and low temperature performance as well as affect sorting,asphalt types > freeze-thaw cycles > de-icing salt concentration.Comprehensive consideration of high and low temperature properties determines the best performance is WJH mixture.According to the environmental characteristics of the central and western regions of Inner Mongolia,and considering the high temperature rut on the harm is bigger,so chose the selection of WJH mixture which high temperature performance is good and the low temperature performance is not much different from the WJ60 mixture for further analysis.Through the experimental data analysis of WJH and JH mixture of high and low temperature performance,the result shows that SDYK warm mixing agent to join more significantly enhanced rubber powder modified asphalt mixture of high and low temperature performance.The WJH and JH mixture of high and low temperature performance are gradually reduced with the increase of freeze-thaw cycles.De-icing salt accelerated freeze-thaw cycle of damage to the asphalt mixture and 8% of deicing salt concentration had the greatest influence.SDYK agent to join slows down the frozen circulation and salt damage to the mixture.But through the high and low temperature performance experiment found that the destruction of WJH mixture in the freezing and thawing cycle is greater than that of JH.