With the rapid development of municipal engineering, the technology and scheme for the quality control of asphalt pavement concrete are becoming more and more perfect. In order to rush for work and time, paving constr...With the rapid development of municipal engineering, the technology and scheme for the quality control of asphalt pavement concrete are becoming more and more perfect. In order to rush for work and time, paving construction of some asphalt pavements is becoming more and more common in cold winter. In order to ensure the compaction quality of asphalt concrete during construction under low temperature conditions, the application of warm mix is more and more common. In this paper, SMA-13 is taken as the research object, through the comparative experimental study of different temperatures and whether warm-mix agent is added, it is found that warm-mix agent can greatly improve the compaction quality of SMA-13 under low temperature conditions, and continuous improvement of warm-mix agent technology provides a strong guarantee for asphalt concrete construction under cold conditions.展开更多
In this paper, the research on warm mix asphalt construction technology of asphalt surface course in low temperature season in cold areas is carried out. The research project is guided by surface theory, mortar theory...In this paper, the research on warm mix asphalt construction technology of asphalt surface course in low temperature season in cold areas is carried out. The research project is guided by surface theory, mortar theory, strength theory and asphalt concrete regulations, based on solid engineering practice, aiming at breaking through the bottleneck of Asphalt Mixture Construction under low temperature environment, through repeated tests and optimization. Carry out a series of studies including the selection of warm mix agent, the formula, road performance and construction technology of warm mix asphalt mixture, and start from four aspects: the selection of warm mix agent, the proportion and technology of warm mix asphalt mixture, the road performance of warm mix asphalt mixture and the construction technology of warm mix asphalt mixture expressway. It has formed a complete set of technical scheme and control standard system for selecting and determining the optimal type and dosage of warm mix agent, reasonable raw material ratio, mixing process and parameters, road performance and applicability of warm mix asphalt mixture, and construction of warm mix asphalt process in low temperature season of asphalt pavement engineering.展开更多
Foamed asphalt typically relies on water as a foaming agent because water becomes gaseous at elevated temperatures, generating numerous tiny bubbles in the asphalt and causing spontaneous foaming. In this study, ethan...Foamed asphalt typically relies on water as a foaming agent because water becomes gaseous at elevated temperatures, generating numerous tiny bubbles in the asphalt and causing spontaneous foaming. In this study, ethanol was used as a potential alternative to water as a foaming agent. Ethanol is expected to be a physical blowing agent in the same manner as water, except it requires less energy to foam due to its 78 ℃ boiling point. This study compares the performance of water and ethanol as foaming agents through the measurements of rotational viscosity, the reduction in temperature during foaming, and volatile loss. The ethanol-foamed asphalt binders were prepared at 80 ~C and 100 ~C, while the water-foamed asphalt binders were prepared at 100 ~C and 120 ~＇C. Additionally, the rolling thin film oven （RTFO） was used to generate short-term aging of the foamed asphalt binders. A rotational viscometer was used to determine the viscosity of the asphalt binders at 80 ~C, 100 ~C, 120 ~C, 140 ~C, and 160 ~C. Overall, ethanol can function in the same manner as water but requires less energy to foam. It is proven based on the smaller drop in temperature of the asphalt binder foamed using ethanol compared with that prepared with water. This is due to the lower latent heat capacity of ethanol, which requires less energy to vaporize compared with water. Through the rotational viscometer test, ethanol performs better in lowering the viscosity of asphalt binders, which is essential in allowing produc- tion processes at low temperatures, as well as a better workability and aggregate coating. Ethanol can be expelled from the foamed asphalt binders at a higher rate due to its lower boiling point and latent heat.展开更多
文摘With the rapid development of municipal engineering, the technology and scheme for the quality control of asphalt pavement concrete are becoming more and more perfect. In order to rush for work and time, paving construction of some asphalt pavements is becoming more and more common in cold winter. In order to ensure the compaction quality of asphalt concrete during construction under low temperature conditions, the application of warm mix is more and more common. In this paper, SMA-13 is taken as the research object, through the comparative experimental study of different temperatures and whether warm-mix agent is added, it is found that warm-mix agent can greatly improve the compaction quality of SMA-13 under low temperature conditions, and continuous improvement of warm-mix agent technology provides a strong guarantee for asphalt concrete construction under cold conditions.
文摘In this paper, the research on warm mix asphalt construction technology of asphalt surface course in low temperature season in cold areas is carried out. The research project is guided by surface theory, mortar theory, strength theory and asphalt concrete regulations, based on solid engineering practice, aiming at breaking through the bottleneck of Asphalt Mixture Construction under low temperature environment, through repeated tests and optimization. Carry out a series of studies including the selection of warm mix agent, the formula, road performance and construction technology of warm mix asphalt mixture, and start from four aspects: the selection of warm mix agent, the proportion and technology of warm mix asphalt mixture, the road performance of warm mix asphalt mixture and the construction technology of warm mix asphalt mixture expressway. It has formed a complete set of technical scheme and control standard system for selecting and determining the optimal type and dosage of warm mix agent, reasonable raw material ratio, mixing process and parameters, road performance and applicability of warm mix asphalt mixture, and construction of warm mix asphalt process in low temperature season of asphalt pavement engineering.
基金the National Science Foundation(NSF),which funded a research grant through the SusChem/Collaborative Research Program(award number: 1300286)
文摘Foamed asphalt typically relies on water as a foaming agent because water becomes gaseous at elevated temperatures, generating numerous tiny bubbles in the asphalt and causing spontaneous foaming. In this study, ethanol was used as a potential alternative to water as a foaming agent. Ethanol is expected to be a physical blowing agent in the same manner as water, except it requires less energy to foam due to its 78 ℃ boiling point. This study compares the performance of water and ethanol as foaming agents through the measurements of rotational viscosity, the reduction in temperature during foaming, and volatile loss. The ethanol-foamed asphalt binders were prepared at 80 ~C and 100 ~C, while the water-foamed asphalt binders were prepared at 100 ~C and 120 ~＇C. Additionally, the rolling thin film oven （RTFO） was used to generate short-term aging of the foamed asphalt binders. A rotational viscometer was used to determine the viscosity of the asphalt binders at 80 ~C, 100 ~C, 120 ~C, 140 ~C, and 160 ~C. Overall, ethanol can function in the same manner as water but requires less energy to foam. It is proven based on the smaller drop in temperature of the asphalt binder foamed using ethanol compared with that prepared with water. This is due to the lower latent heat capacity of ethanol, which requires less energy to vaporize compared with water. Through the rotational viscometer test, ethanol performs better in lowering the viscosity of asphalt binders, which is essential in allowing produc- tion processes at low temperatures, as well as a better workability and aggregate coating. Ethanol can be expelled from the foamed asphalt binders at a higher rate due to its lower boiling point and latent heat.
