Effects Of Various Waste Cooking Oils On The Regeneration Performance Of Aged Asphalt

Using waste cooking oils to regenerate the waste asphalt mixture can recycle the waste material and turn it into treasure,which is also a research direction in the field of road materials.However,the existing study uses one single type of waste cooking oil,and mostly for laboratory simulation of aged asphalt regeneration,the study on pavement recycled asphalt is less involved.In this study,three aged asphalts are used,which are the pavement recycled asphalt extracted from aged asphalt mixture and two kinds of laboratory simulated aged asphalt with different degrees.The effects of different waste cooking oils on the basic physical properties,rheological properties and chemical composition of different aged asphalt were studied.Three waste cooking oils and one unused oil were added into the recycled aged asphalt to prepare the rejuvenated asphalt.After the performance test and analysis,two waste cooking oils were selected to add into the simulated aged asphalt and the performance study was carried out.The main conclusions are as follows:(1)The addition of waste cooking oils increase the penetration and ductility of asphalt,reduce the softening point and viscosity of asphalt,and the physical properties of asphalt are not proportional to the amount of waste cooking oils.For the same kind of aged asphalt,different waste cooking oils require different optimal dosage when regenerating asphalt.When the target level of rejuvenated asphalt is determined to a certain range,different waste cooking oils have the same applicable dosage.(2)The results of dynamic shear rheological test show that the complex shear modulus of asphalt decreases and the phase angle increases with the addition of waste cooking oils,and the values and changing trend of complex shear modulus and phase angle of recycled asphalt are approximately the same when different waste cooking oils are added in the same amount;the rutting factor and cracking factor of rejuvenated asphalt of waste cooking oils decrease with the increase of the amount of waste cooking oils.The values and changing trend of the rutting factor and cracking factor with the same waste cooking oil at same amount are similar.(3)The results of four component test and infrared spectrum test show that the addition of waste cooking oils can adjust and improve the composition and content of aged asphalt.The specific performance is that the relative content of aromatics in aged asphalt increases and the relative content of asphaltene decreases.At the same time,carbonyl factor and sulfoxide factor decreased.In addition,when the aging degree of asphalt is low,the composition and content of rejuvenated asphalt are closer to the target range.