Study On Preparation Of Reducing Heat Storage Asphalt Mixture

City roads stand a big proportion of city underlying surface. Asphalt pavement material is grey body close to black body. It is one of the important heat sources of urban heat island effect with high speed of absorbing heat and high thermal capacity. Development and manufacture of pavement material with function of thermal radiation which can reduce heat storage of road surface and decrease pavement temperature have the important meaning to reducing asphalt pavement high-temperature diseases and diminishing urban heat island effect.Infrared powder material according with the demands is prepared and selected by experiment. Surface treating the powder is to improve activity of powder. Through observing distribution of infrared powder in basic asphalt by SEM, compatibility between infrared powder and asphalt is analyzed in microscopic scales.As functional filler, treated infrared powder is incorporated into asphalt mixture by substituting a part of mineral powder. With this method, reducing heat storage asphalt mixture is prepared. The experiment result show that selected infrared powder has high emission rate in atmospheric infrared windows,which ensure that the mixture that prepared with infrared powder has a better self-radiating heat function.The paper does the research on thermal radiation properties of reducing heat storage asphalt mixture by experiment. The results show that surface temperature of JCLJ infrared powder asphalt mixture is 3.4℃lower on the average than common asphalt mixture, which indicate that the mixture has a better temperature reduction performance.The paper does the research on normal road performance of reducing heat storage asphalt mixture including high temperature stability, low temperature crack resistance and water stability by experiment. The results show that dynamic stability of JCLJ infrared powder asphalt mixture increases by 9.52%,and residual marshall stability of the mixture increases by 3.67%, compared with common asphalt mixture. The results indicate that the mixture doesn't decrease normal road performance of asphalt mixture.The paper analyzes that influence of reducing heat storage asphalt mixture effect on urban heat island effect with theory. Computing model is given. The paper figure out that JCLJ infrared powder asphalt pavement can lower the temperature of the surface layer atmosphere by 3.03℃, which reveals cooling mechanism of this mixture.