Research On Properties And Mechanism Of Low-viscosity Rubberized Asphalt Based On Waste Engine Oil

Defects such as high viscosity and poor storage stability are the main reasons that the widespread application of ordinary rubberized asphalt remains restricted.At the same time,the mixture construction process is notoriously accompanied by a lot of irritating odor and smoke,which does not meet the current environmental protection requirements.Therefore,with the continuous improvement of resources,high efficiency and the concept of double carbon,it is of great practical significance to improve the research on the aforementioned problems of ordinary rubber asphalt.The specific work of this paper is as follows:(1)The preparation parameters of rubber asphalt after mixing it with waste engine oil were studied.It was found that the influence of waste engine oil on the performance of rubber asphalt at different recovery times is small,but that the adding order of waste engine oil is closely related to rubber asphalt.It is thus recommended that the rubber asphalt be prepared by pre blending waste engine oil with rubber powder.The four-factor and four-response test was developed by the response surface method,and the preparation parameters of the low-viscosity rubberized asphalt in this paper were proposed as follows:the content of waste engine oil is 3.5%,the shear rate is 5000 r/min,the shear temperature is 180℃,and the shear time is 1h.(2)Compare and analyze the difference between low-viscosity rubber asphalt,base asphalt,devulcanized rubber asphalt,and ordinary rubber asphalt,in terms of basic properties,storage stability,and rheological properties.The results show that adding waste engine oil can improve the low temperature properties,anti-aging properties,storage stability and low temperature rheological properties of rubber asphalt.In addition,waste engine oil also led to significant improvements in the viscosity of rubber asphalt.Furthermore,compared with ordinary rubber asphalt,low-viscosity rubber asphalt can reduce the mixing temperature of the mixture by 37.5℃,and the compaction temperature by 27.5℃.(3)By means of scanning electron microscopy and infrared spectroscopy,the interaction mechanism between waste engine oil,rubber powder and asphalt was analyzed.The results show that the rubber powder treated with waste engine oil had a fluffy surface,the light oil in the asphalt phase was more likely to enter the rubber particles,and it was easier to disperse uniformly in the asphalt under the action of high temperature and high-speed shearing,which improved the compatibility between the rubber powder and the asphalt.In addition,the preparation process of low-viscosity rubberized asphalt was determined to be similar to that of ordinary rubberized asphalt,and the rubber powder mainly swells in the asphalt.(4)Molecular dynamics simulation of rubber asphalt and low-viscosity rubber asphalt was carried out,and the viscosity reduction mechanism of low-viscosity rubber asphalt was further explained from the perspective of microscopic molecular motion.The dispersion of rubber molecules in the low-viscosity rubber asphalt system was better than that of ordinary rubber asphalt,and the rubber powder in its internal structure was not easy to agglomerate.In addition,the fluidity of each component of low-viscosity rubber asphalt was enhanced,indicating that the addition of waste engine oil reduced the viscosity of rubber asphalt.