Research On Performance Of Low-carbon And Energy-saving Mix Asphalt Based On Cooling Characteristics

The hot mix asphalt consumes a lot of energy and produces toxic gases during the mixing process with a high temperature.In the meantime,an excessive heat can cause the aging of the asphalt and affect the performance of the mixture.While the cold mix asphalt has certain advantages in the aspects of the energy consumption and environmental friendly,but its performance can't up to the standard of the hot mix asphalt,therefore it can't be widely used in road construction.To solve this problem,based on the research and summary of the domestic and foreign related technologies,this paper studies the relative performance of low-carbon and energy-saving mix asphalt which is based on the cooling characteristics and the reliability of this technology is verified by engineering applications.Low-carbon and energy-saving mix asphalt is a new kind of mix asphalt compared to the same type of hot mix asphalt which is able to reduce the construction temperature of asphalt mixture,improve the compaction degree,increase the transportation distance and extend the construction period by technical means without changing the proportion design of the mixture and reducing the performance of the mixture.Based on test of coarse and fine aggregate,mineral powder,asphalt binder and additive performance,the paper selected a surface active additive and conducted a mix design of low-carbon and energy-saving mix asphalt.The study has chosen the Liaohe No.90 matrix asphalt and SBS modified asphalt and determined the mineral aggregate gradation of mixture and the optimum asphalt content.Through the compaction curve of porosity and temperature,the paper obtained that the mixing temperature of low-carbon and energy-saving mix asphalt has reached more than 300? of the temperature drop range compared to the corresponding hot mix asphalt.Study has shown that low-carbon and energy-saving mix asphalt has the compaction characteristic and cooling characteristic so that it is capable of forming an insensitive temperature range.Moreover,it can obtain more than twice the effective compaction time because of its lower cooling rate.By testing the recycled asphalt ductility,softening point and viscosity index,the paper found that the low-carbon and energy-saving technology can reduce the degree of aging of the asphalt which helps to obtain a good road performance and to ensure the durability of asphalt pavement.The pavement performance of AC-13 and SMA-13 low-carbon and energy-saving mix asphalt are researched by comparing with corresponding hot mix asphalt.The test results showed that all indexes of the two kinds of asphalt mixture which added the additive meet the specification requirements.The high-temperature stability,water damage resistance and anti fatigue performance of asphalt mixture are improved to some extent.The analysis of energy saving and economic benefits show that the low-carbon and energy-saving mix asphalt could reduce the energy consumption above 20%and the emission of harmful gas above 50%compared to the hot mix asphalt.Keeping the unchanged conditions of the performance,the price per ton of the new mixture and the hot mixture are essentially flat.The results of road engineering application and testing show that the new material is convenient to construct,and it could extend the construction period,make less pollution,consume low energy,has stable performance and excellent pavement condition etc.It can be widely used in pavement construction.