Research On Anti-UV Aging Performance Of Recycled Asphalt With Waste Vegetable Oil

As a kind of low viscosity oil,the waste vegetable oil,which has the characteristics of low viscosity,high saturation and large volume.The recycled waste vegetable oils was used to develop rejuvenators,recycled asphalt and mixes,and its road performance meets the requirements for pavement use.However,the unsaturated carbon chain in vegetable oils is susceptible to ultraviolet light and is oxidized to deteriorate.Whether waste vegetable oil recycled asphalt can withstand the test of ultraviolet light in the course of long-term use is still not known,therefore,it is necessary to carry out in-depth research on its anti ultraviolet aging properties.First,in order to quantitatively simulate the effect of ultraviolet light irradiation on waste vegetable oil recycled asphalt,the asphalt accelerated simulation ultraviolet aging equipment was developed,and the test parameters of asphalt accelerated ultraviolet aging were determined:temperature was 60?,ultraviolet light intensity was 141w/m~2,The asphalt film thickness is 200?m and the indoor ultraviolet aging time equivalent acceleration rate is 10times,and the accelerated simulated ultraviolet aging test method is established.Secondly,based on the preliminary research results of the subject group,6%is the best dosage to prepare the recycled asphalt.Through the test of three physical indexes and rheological properties of asphalt,compared with the original bitumen and mineral oil recycled asphalt,the ultraviolet aging resistance of waste vegetable oil recycled asphalt was analyzed from macroscopic angle.After ultraviolet aging,the composition of asphalt molecule and waste vegetable oil was oxidized and condensed,which increased the content of asphaltene,and the high temperature performance of waste vegetable oil recycled asphalt increased slightly and the fatigue performance decreased slightly.Waste vegetable oil recycled asphalt after ultraviolet aging 10?delay value is only 11.0cm,the residual ductility value is 28.2%,the temperature drops to-18?,the waste vegetable oil recycled bitumen after ultraviolet aging the m-value is less than the 0.3,s value,the low-temperature performance no longer satisfies the low temperature performance requirement in the SHRP specification,Compared with the original asphalt and mineral oil recycled asphalt,its low temperature performance decreased most significantly.Thirdly,in order to reveal the decay mechanism of waste vegetable oil recycled asphalt under ultraviolet illumination,by using four component analysis method and IR analysis method,from the composition of the asphalt and the change of the functional group,the index of Ic of the gel index,the percentage of component change B,the carbonyl functional group index CI and the sulfoxide functional group exponent Si were evaluated.,the influence of ultraviolet aging on the microstructure of recycled vegetable oil was analyzed.After ultraviolet aging,the recycled asphalt from the waste vegetable oil changed from the Sol type to the gel type,the content of asphalt increased;At the same time,in the same ultraviolet irradiation,the percentage change of recycled asphalt component B and the Sulfoxide group Index SI is higher than the original asphalt and mineral oil recycled asphalt,the asphalt has the most aging products and the performance influence is most significant.Finally,aiming at the problem of poor low temperature performance and anti-ultraviolet aging ability of waste vegetable oil recycled asphalt after ultraviolet aging,a compound improvement scheme was proposed to improve the anti ultraviolet aging performance and low temperature performance.The performance improvement of waste vegetable oil recycled asphalt was optimized by using hindered amine(HALS)as light stabilizer and SBS compound modification method through indoor performance evaluation.