Study On Performance Of Double-warm-mix Asphalt And Its Mixture Based On Water Foaming And Warm-mix Additives

At present,warm-mix asphalt technology is widely used at home and abroad This technology is mainly to reduce the temperature of asphalt mixture mixing and paving by mixing the asphalt with a warm-mix additive or foaming the asphalt,thereby saving energy reduce emissions.According to the previous research experience,the temperature of warm-mix asphalt with warm-mix additive technology is relatively large,but the cost of warm-mix additive is relatively high.The cost of foamed asphalt is much lower,but the cooling effect is not as good as that of warm-mix asphalt with the addition of warm-mix additive technology.Combines the low mixing temperature of the warm-mix additive technology and the low cost of the foaming technology,the warm-mix additive is added to the asphalt and stirred thoroughly to prepare the warm-mix additive asphalt,which is then foamed by the foaming equipment to obtain the warm-mix additive foamed asphalt,also known as double-warm-mix asphalt.In this study,three warm-mixing additives Sasobitbit,M1,1102 were selected,and the indoor double-warm-mix asphalt was self-made.The effects of different double-warm-mix technologies on the performance of asphalt and its mixture were studied.First,determine the three major indexes and the viscosity at 135 ℃ of various double-warm-mix asphalt before and after RTFOT aging.Then,using SUP-20 asphalt mixture gradation to study the cooling effect of each warm mix technology.Next,through relevant experiments,the high temperature performance,low temperature performance,water damage resistance and fatigue performance of the double-warm-mix asphalt mixture were studied.Finally,based on the grey correlation analysis,comprehensive evaluation of cooling effect and various road performance,the ten warm-mix technologies studied in this paper.The research results are as follows:(1)the softening point,viscosity at 135 ℃,and the penetration at 25 ℃ and the elongation at 5 ℃ of the various double-warm-mix asphalts are significantly lower than those of the asphalts with only the warm-mix additive.After aging,the quality loss of various double-warm-mix asphalt and single foamed asphalt does not meet the specification requirements,and the performance is basically the same as that of the unfoamed asphalt after aging(2)the original asphalt+0.5%M1+ foaming has the best cooling effect,and the cooling range is about 47 ℃.The cooling effect of each double-warm-mix technology is better than the corresponding single-warm-mix technology,and the cooling effect of the double-warm-mix technology that reduces the amount of warm-mix additive by half is also the same as the recommended single warm-mix additive technology The difference is almost the same,achieving the purpose of being more environmentally friendly and economical.(3)the decrease in compaction temperature does not affect the various road performance of the asphalt mixture.Compared with the corresponding single warm-mix technology,the double-warm-mix technology has very little effect on the high temperature performance,low temperature performance,water damage resistance and fatigue performance of the asphalt mixture.(4)the original asphalt+0.5%M1+foaming is the best warm-mix technology,and all the warm-mix technologies are better than ordinary Hot mix,all the recommended double-mix temperature mixing technologies are superior to the corresponding single warm-mix technology,and the double-warm-mix technology that reduces the amount of warm mix by half is generally has a small difference from recommended single warm-mix additive technology.