Research On Durability Performance Of Hot Recycling Modified Asphalt Mixture Based On Homemade Recycling Agent

Since the early 1990 s,as China’s rapid economic development,the number of highway has been unable to meet the current situation of development,China will build up thousands of highway just a 10-year period,especially asphalt pavement.But so far,many roads have entered the stage of overhaul.Among them,SBS modified asphalt accounts for about 15% of the total road asphalt.Pavement reconstruction will produce a large amount of waste SBS modified asphalt mixture,which is difficult to stack,and improper handling will inevitably cause a lot of waste of resources.And pollution of soil and water sources.Therefore,the recycling of asphalt pavements in my country should receive more attention and development.This can effectively recycle resources to achieve the purpose of saving asphalt costs and protecting the environment.Based on the regeneration mechanism and theoretical basis of the waste asphalt mixture,this paper first selects the appropriate regenerating agent composition material,and then calculates and analyzes the blending ratio of the regenerant composition material through the response surface design method,establishes the response regression surface model,and optimizes the solution.The product formula of regenerating agent,combined with related test procedures and technical standards,select several common regenerating agents on the market and self-made regenerants for routine performance test comparison,analyze the performance of self-made regenerants and determine its optimal dosage,and then pass FTIR,DSR,DSC,MSCR,force ductility and other related tests verify the regeneration mechanism and effect of the self-made regenerant from various aspects.The comprehensive mechanical properties of the recycled asphalt materials are studied.The test results show that the self-made regenerant is compared with other several This kind of regenerant has a good regeneration effect,and its optimal content is determined to be5%.FTIR analysis shows that the regenerant only physically reacts with the aged asphalt,and the regenerant only plays a role of diluting and dissolving,not fundamentally.To change the chemical structure of the aged asphalt,the DSR test shows that although the incorporation of regenerant is beneficial to improve the rheological properties of the regenerated asphalt,it is not conducive to the high temperature shear resistance of the asphalt.The MSCR test shows that the incorporation of the regenerant increases the asphalt’s The elastic deformation reduces the viscous deformation and improves the viscoelasticity of the aged asphalt.The DSC test shows that although the temperature stability of the recycled asphalt cannot be fully restored to the original asphalt level,it is more difficult than the aged asphalt.The temperature stability has been greatly improved.The force measurement ductility test shows that with the gradual increase of the regenerant content,the tensile modulus and yield strain energy of the aged asphalt gradually decrease,and the toughness ratio gradually increases.The low-temperature performance is improved,and through the road performance test,it can be seen that the high-temperature performance of the recycled asphalt mixture is positively correlated with the RAP content,that is,the performance increases with the increase of the RAP content,and the low-temperature performance and water stability performance are It shows a tendency of attenuation,and the maximum content of RAP material is 50%.Through grey correlation analysis,it is found that the correlation between the content of RAP material and the maximum failure strain and the ratio of freeze-thaw splitting strength is relatively high.The fatigue test shows that the asphalt mixture’s The main influencing factors of fatigue performance are temperature and strain level.The comparison found that the influence of strain level on fatigue performance is the main factor,and the fatigue equation based on temperature factor and the fatigue limit equation based on temperature factor have also been established.Finally,the use of recycled asphalt mixture economic and social analysis,found recycled asphalt mixture not only has significant economic benefits and cost savings while also reducing the environmental damage,has good social benefits.