| Coal oil residue is a residue of coal to oil conversion process.It has high additional properties and potential utilization value.The annual output of coal oil residue is huge and difficult to degrade.The burning and stacking will seriously threaten the natural environment and land use space.How to effectively use coal oil residue has become an urgent problem to be solved at this stage.In recent years,a few scholars have used coal oil residue as a bitumen modifier.However,due to the late start of research work,the understanding of coal oil residue is not mature,and further analysis is needed.This paper focuses on the performance characteristics and rheological properties of coal oil residue modified asphalt,the applicable horizon and optimum dosage of coal oil residue,and summarizes the construction control points of coal oil residue modified asphalt mixture.The penetration performance system and SHRP system were used to evaluate the technical performance of coal oil residue modified asphalt.The penetration system showed that coal oil residue can improve asphalt consistency,high temperature performance and shear failure resistance,and is sensitive to low temperature performance and temperature of asphalt.Sexually adverse effects,SHRP system shows that coal oil residue can significantly improve asphalt viscosity,hardness and elastic response ratio,asphalt performance is significantly affected by RTFOT short-term aging.Based on the rheological properties of asphalt,the effects of coal oil residue on the viscoelastic properties of asphalt,high-temperature rutting resistance and fatigue properties were studied by frequency sweep(FS),multiple stress creep recovery(MSCR)and linear amplitude sweep(LAS).The results show that the coal oil residue will reduce the strain peak in the viscoelastic range of the asphalt line,shorten the stress-strain lag time,significantly improve the high-temperature anti-rutting ability of the asphalt and the traffic applicable grade,and improve the asphalt fatigue performance.By comparing the road performance of different grades(AC-13,AC-16,AC-20)matrix asphalt mixture and coal oil residue modified asphalt mixture,according to the characteristics of each layer and technical performance requirements,analysis It is concluded that the reasonable application level of coal oil residue is the middle layer.In order to explore the impact of coal oil residue on asphalt pavement performance and the best use of the amount,the road performance of different coal oil residue modified asphalt mixture was compared.The results show that: coal oil residue can significantly improve the high temperature performance of asphalt pavement and improve water resistance,but it will weaken the low temperature crack resistance of asphalt pavement;comprehensive analysis shows that the recommended blending amount of coal oil residue is 15%,for heavy load Traffic sections can be appropriately increased to 20%.According to the paving conditions of the test road,technical control points are proposed for the key processes such as mixing,paving and rolling of coal oil residue modified asphalt mixture,which provides engineering reference basis for efficient green utilization of coal oil residue. |
