Research On The Composite Applications Between Stabilized Asphalt Rubber And Techology Of Hot Recycling In Plant

At present,adding regenerative agent has become the main way to regenerate asphalt mixture.However,it increases the regeneration procedure,because it needs to add the regenerative agent particularly.In addition,the properties of the regenerated asphalt mixture are insufficient,and the content of reclaimed asphalt pavement(RAP)is usually low.This paper has studied the composite application of stabilized asphalt rubber and hot recycling technology,and it is carried out from the perspective of composite mechanism,cementation material performance,mixture design method and performance,production technology and so on.Firstly,from the microscopic point of view,this paper analyzed the changes of the functional group,the molecular weight distribution,the surface morphology and the nanoscale adhesion force of asphalt before and after the regeneration.The result of infrared spectroscopy showed the changes of the functional group of stabilized asphalt rubber and its regeneration.It shows that the rubber powder and asphalt were mainly physically blended,accompanied by a weak chemical reaction during the modification and regeneration of stabilized asphalt rubber.And The result of Gel Permeation Chromatography shows that the content of macro-molecular material has decreased while the small molecular content has increased during regeneration process,but the overall transformation range was not large,and there was no obviously change.Then,stabilized asphalt rubber and its regeneration were studied at the micro level based on the atomic force microscope,the result shows that the honeybee structure disappeared,and the adhesion strength of regenerated asphalt rose steadily with the increase of the content of the stabilized rubber asphalt.Secondly,this paper has made a comprehensive performance analysis on the asphalt binder,and studied the change of the properties of the regenerated asphalt.Through the analysis of the conventional index,it was found that the penetration and ductility of bitumen were dropping and the softening point was raising while the aging was growing on.Different from the situation of using regenerative agent,the result shows that the penetration was dropping,the softening point was slightly raising,the ductility of 5 C and 15 C was obviously improved and the elastic recovery changed,when regenerating the stabilized asphalt rubber.It indicates that rubber asphalt provides a certain low temperature performance and anti-deformability to aging asphalt.The results of dynamic shear rheology test show that the regeneration of stabilized rubber asphalt didn't reduce its high temperature performance.Instead the excellent viscoelasticity of rubber asphalt could make RAP meet the performance requirements under higher temperature environment.And the results of the BBR test show that the low temperature performance of regenerate asphalt mixture using stable rubber asphalt is also improved to a certain extent.Thirdly,through the laboratory test,the paper has analyzed the gradation changes of the mixtures used in the pavement.Also,it has studied the design method of the design of mix proportion of the stabilized rubber asphalt mixture.It has analyzed the regulars of properties change by comparing the asphalt aggregate ratio of regenerated asphalt mixture with different contents of RAP,and the sensitivity of regenerated asphalt mixture to the asphalt content.Also,it has taken the methods of adding regenerative agent to improve the properties further and changing the content of regenerative agent to meet specific needs of the regenerated asphalt mixtures.Finally,based on the production engineering of the stabilized rubber asphalt mixture,this paper has analyzed the algorithm to identify the components of the regenerated asphalt mixture,and established the evaluation system and index of the uniformity of mixture components by making analysis on the pictures scanned by X-ray.Besides it has determined the optimum mixing time and the temperature range of the stabilized rubber asphalt mixture through the evaluation of the uniformity of each component.