The performance evaluation and chemical property analysis of the recycled warm mix asphalt (RWMA) binders containing 100% artificial reclaimed asphalt ( RA) are presented, and the combined effects of different p...The performance evaluation and chemical property analysis of the recycled warm mix asphalt (RWMA) binders containing 100% artificial reclaimed asphalt ( RA) are presented, and the combined effects of different percentages of the rejuvenator and warm mix additive (WMA) additives on RWMA binders are analyzed through laboratory tests. Three types of WMA additives ad one commercial rejuvenator named GST were selected to restore the artificial RA. The laboratory performace tests including the penetration test, softening test ad rotary, viscosity (RV) test were carried out. In addition, the Fourier transform infrared spectroscopy (FTIR) test was performed to explore the chemical property of RWMA binders. The results of the performance tests indicate that the rejuvenator GST has the ability to restore the artificial RA; choosing the optimum content of WMA additives and rejuvenator is the key to restoring 100% artificial RA, since the combined effects of them play an important role in determining the basic laboratory performance of RWMA binders. The FTIR tests show that the process of recycling mainly adjusts the chemical component of aged asphalt and no remarkable change is observed in the FTI1R spectra of RWMA binders in terms of chemical functional groups with the introduction of WMA additives.展开更多
The rutting and low-temperature resistances of warm-mix recycled asphalt binders under the secondary aging condition were measured by the dynamic shear rheometer test and bending beam rheometer test.Effects of differe...The rutting and low-temperature resistances of warm-mix recycled asphalt binders under the secondary aging condition were measured by the dynamic shear rheometer test and bending beam rheometer test.Effects of different types of warm-mix asphalt(WMA)technologies and additives were evaluated.Aging and improvement mechanisms were investigated by the Fourier transform infrared spectroscopy test.It is found that recycled binders after the secondary aging are more resistant to rutting and less resistant to low-temperature cracking.The two warm-mix asphalt technologies have opposite effects.Using the Sasobit WMA significantly improves the rutting resistance and reduces the low temperature resistance for the recycled binders due to its morphological change at different temperatures.The rutting factor values of recycled asphalt binders with the Sasobit additive increase by 4.6 to 5.6 times.However,using the Evotherm WMA causes the deterioration of the rutting resistance due to the structural lubrication effect.The rutting factor values of recycled asphalt binders with the Evotherm additive show the reduction of 52%to 62%.It is recommended to add the styrene butadiene rubber latex or crumb rubber powder into the warm-mix recycled asphalt binders to simultaneously improve the rutting and low-temperature cracking resistances.展开更多
基金The National Natural Science Foundation of China(No.50578031)
文摘The performance evaluation and chemical property analysis of the recycled warm mix asphalt (RWMA) binders containing 100% artificial reclaimed asphalt ( RA) are presented, and the combined effects of different percentages of the rejuvenator and warm mix additive (WMA) additives on RWMA binders are analyzed through laboratory tests. Three types of WMA additives ad one commercial rejuvenator named GST were selected to restore the artificial RA. The laboratory performace tests including the penetration test, softening test ad rotary, viscosity (RV) test were carried out. In addition, the Fourier transform infrared spectroscopy (FTIR) test was performed to explore the chemical property of RWMA binders. The results of the performance tests indicate that the rejuvenator GST has the ability to restore the artificial RA; choosing the optimum content of WMA additives and rejuvenator is the key to restoring 100% artificial RA, since the combined effects of them play an important role in determining the basic laboratory performance of RWMA binders. The FTIR tests show that the process of recycling mainly adjusts the chemical component of aged asphalt and no remarkable change is observed in the FTI1R spectra of RWMA binders in terms of chemical functional groups with the introduction of WMA additives.
基金The Natural Science Foundation of Jiangsu Province(No.BK20181404)Qing Lan Project(2016)the Training Plan Project for Young Core Teachers of Nanjing Forestry University(2017).
文摘The rutting and low-temperature resistances of warm-mix recycled asphalt binders under the secondary aging condition were measured by the dynamic shear rheometer test and bending beam rheometer test.Effects of different types of warm-mix asphalt(WMA)technologies and additives were evaluated.Aging and improvement mechanisms were investigated by the Fourier transform infrared spectroscopy test.It is found that recycled binders after the secondary aging are more resistant to rutting and less resistant to low-temperature cracking.The two warm-mix asphalt technologies have opposite effects.Using the Sasobit WMA significantly improves the rutting resistance and reduces the low temperature resistance for the recycled binders due to its morphological change at different temperatures.The rutting factor values of recycled asphalt binders with the Sasobit additive increase by 4.6 to 5.6 times.However,using the Evotherm WMA causes the deterioration of the rutting resistance due to the structural lubrication effect.The rutting factor values of recycled asphalt binders with the Evotherm additive show the reduction of 52%to 62%.It is recommended to add the styrene butadiene rubber latex or crumb rubber powder into the warm-mix recycled asphalt binders to simultaneously improve the rutting and low-temperature cracking resistances.