Study On The Hot In-plant Recycling Design Of Asphalt Mixture

With the development of traffic in our country, traffic volume is increasing rapidly and overload phenomenon becomes more and more serious. Many roads have rutting, cracking and other pavement disease which cannot meet the use requirements any more. These roads which need repainting or overhaul, the overall performance can’t meet the standard, but as the pavement materials still have high value.Based on a practical engineering of a mixing station, hot in-plant recycling technology of asphalt mixture is adopted in this paper. To meet road performance as the prerequisite, maximizing the blending rate of old material by optimizing the design of recycled mixtures and selecting the appropriate performance control indicators.Through the reuse of old material, the technology not only solves the discharge problem, reduces environmental pollution, also saves oil asphalt, aggregate and other scarce resources, which in line with the concept of economy, environmental protection, energy conservation and emissions reduction.The laboratory test as the main research means to determine the best renewable way for the aging asphalt. Due to the influence of aging asphalt, low temperature performance of recycled asphalt mixture is often poor, so this paper emphasis on the evaluation of low temperature performance of recycled asphalt. BBR test proved that the low temperature performance of recycled asphalt can meet the same standard as new asphalt. Using CAS mathematical model and Burgers mechanics model to fit creep stiffness data of BBR test with MATLAB software. Results show that both have high fitting precision.Determine the old material blending rate basing on the regeneration of aging asphalt. Making AC-16as target regeneration grade, two gradation curves and two adding ways of regeneration agent as the main variables can design four testing schemes. Getting the best way to regenerate through road performance test. Finally the old mixture regeneration scheme is used to guide the asphalt mixture production in plant.