Study On Recycled Asphalt Of Asphalt Pavement Hot In Place Recycling In Hainan Expressway

The Hainan eastern expressway has been operating 10 years since 1998. Pavement wearing serious are confronting with the needs of vast repairs, which, of great deal, require maintenance or even totally restructuring. It is imperative to recycling the waste asphalt mixture so as to protect environment and perserve resource. Hence, this has caused a major question that we are currently attempting to figure out the hot in-place recycling mix technology.,Firstly extracting the used ordinary asphalt and the used modified asphalt, then integrated using four components analysis, FTIR, softening point,penetration,ductility,Viscosity and DSR to assess their age and study the aging mechanism.Based on the results of used asphalt,the experiment has been conducted through extracting the ordinary asphalt and the modified one. Two recycling agents(OP—900 and OP—1100) from the Hainan Eastern Line Company and two others (Sb—1 and Sb—2) from Haichuan Company are applied to recycling the used asphalt.The OP—900 recycling agents are poured into the used asphalt with the percentages of 5.77%, 7.55%, 10.91%, 15%, 30%, 35%, 40%,and then test their components softening point, penetration, ductility, viscosity and DSR. The Sb—1 recycling agents are poured into the used bitumen with the percentages of 4.08%,10.2%,12.24%,16.33%,20.4%,30%,and then test their components softening point, penetration, ductility, viscosity and DSR. With the results of test,we finally decide to use the OP—900 recycling agents in percent of 30%.The OP—1100 recycling agents are poured into the modified used asphalt with the percentages of 8%, 10.91%,14.04%,16%,18.33%,24%,30%,35%,40%,and then test their components softening point, penetration, ductility, viscosity and DSR. The Sb—2 recycling agents are poured into the modified used asphalt with the percentages of 6.11%,8.2%,12.24%,16.33%,24.5%,30%,35%,40%,and then test their components, softening point, penetration, ductility, viscosity and DSR. Comparing with the results, we can choose appropriate recycling agents with appropriate proportion. With the results of test, we finally decide to use the Sb—2 recycling agents in percent of 40%.With FTIR test the used asphalt with the percentages of 30% OP—900 recycling agents and the used modified asphalt with the percentages of 40% Sb—2 recycling agents,we can make the conclusion that recycling agents have not chemical reaction with used bitumen.Through extensive theoretic research and vast indoor and outdoor experiments analysis, concerning the actual situation of the left-side road of the route from Fucheng to Qionghai, a section of the Hainan eastern expressway, based on the experiments, assessments and investigations on the situation of used roads and bitumen materials, we could determine the kinds of rejuvenating agent and it's amount.