Study On Performance Of Reclaimed Asphalt And Asphalt Mixture Mixed With Ground Temperature

With high quality development of road construction,under the background of energy shortage and energy saving and emission reduction needs,road maintenance was faced with huge challenge in our country,which was needed to find a low carbon environmental protection road maintenance technology,while warm mix technology and in-situ regeneration technology fusion,which not only reduces energy consumption and carbon emissions,but also realizes in-situ recycling of road materials,which has good social and environmental benefits.Therefore,in this paper,the reclaimed asphalt is extracted from the waste asphalt mixture and added with regenerator for regeneration.Sasobit,Evotherm M-1 and YDWB-1,three kinds of warm mixing agents independently developed in China,are selected to study the warm mixing modification of reclaimed asphalt and its mixture.Based on asphalt conventional performance test,asphalt rheological behavior test and pavement performance test,the asphalt high and low temperature properties,asphalt rheological properties and pavement performance of warm mix reclaimed asphalt and warm mix reclaimed asphalt mixture were studied.Through the ground temperature mixing recycled asphalt mixture test road,the practical application effect of ground temperature mixing recycling technology is studied,and based on the construction process of the test road,the LCA analysis method is used to compare and analyze the energy saving and emission reduction effect of ground temperature mixing recycling technology.The main research results and conclusions are as follows:(1)Y-type regenerator does not affect the influence law of warm mix agent and mixture amount of warm mix agent on recovered asphalt,and there is a good adaptability between warm mix agent and Y-type regenerator.Sasobit and YDWB-1 warm mix have obvious viscosity reduction effect on asphalt,while Evotherm M-1 warm mix has small viscosity reduction range.(2)Sasobit can improve the high temperature performance,increase the linear viscoelastic range of asphalt,but reduce the fatigue resistance and low temperature performance of asphalt;Evotherm M-1 warm mix agent can improve the rutting resistance of asphalt at high temperature,improve the fatigue resistance of asphalt slightly,but it will reduce the linear viscoelastic range of asphalt and low temperature performance.YDWB-1 can reduce the high temperature performance and linear viscoelastic range of asphalt,but can improve the fatigue resistance and low temperature performance of asphalt,and enhance the creep recovery ability of asphalt.(3)By comprehensive analysis of the influence of warm mix agent on the basic properties of reclaimed asphalt and rheological behavior at high and low temperatures,it can be seen that the optimal mixing amount of Sasobit,Evotherm M-1 and YDWB-1 warm mix agent is 3%,1.0%and 1.0%,respectively.The 1.0%YDWB-1 warm mix agent was combined with 2%Sasobit warm mix agent and 1.0%Evotherm M-1 warm mix agent,respectively,which had a certain superposition effect on the high temperature and low temperature performance of reclaimed asphalt.(4)In terms of pavement performance of the mixture,three kinds of warm mix can improve the water stability of the reclaimed asphalt mixture;Evotherm M-1 and Sasobit warm mix can improve the high temperature stability of reclaimed asphalt mixture,reduce the low temperature crack resistance of the mixture;While YDWB-1 warm mixing agent can reduce the high temperature stability of reclaimed asphalt mixture,and the stiffness of YDWB-1-Wram is small,which can enhance the cracking resistance of the mixture at low temperature.(5)In the case of winter construction and less than one heating equipment,the paving effect of three kinds of in-situ reclaimed asphalt pavement is ranked as follows: S-test road of mixing reclaimed asphalt with ground temperature > Y-test road of mixing reclaimed asphalt with ground temperature > geothermal reclaimed asphalt pavement.The results show that the addition of warm mixture can improve the quality of local reclaimed asphalt pavement,and can still be normal construction when the ambient temperature is low in winter,and prolong the maintenance period of local reclaimed asphalt road.(6)The quantitative analysis results of energy conservation and emission reduction show that the geothermal mix regeneration technology can directly save a lot of energy,reduce a lot of carbon emissions,energy conservation and emission reduction effect is remarkable,with good economic,social and environmental benefits.