Research On Preparation And Properties Of CFPCM Using In Asfalt Mixture

Though being widely used in highway and urban roads, the asphalt pavement faces with some of the diseases associated with temperature, especially low temperature cracking, rain and snow-caused diseases. For a long time, people were passive to response to the challenge that asphalt pavement meets in application, but the effect was limited. This paper focuses on the way to preparation technology of the phase change materials for asphalt mixture, which bases as phase change materials in the application of asphalt mixture.On basis of technical requirements of the phase change materials for asphalt mixture, the essay determines alkenes phase change materials appropriate at low temperature, combined with the effective work temperature of asphalt pavement. Phase change materials based on areas of application architecture for direct ion of existing asphalt mixture by physical adsorption on the amorphous. According to the existing studies about the application of the phase change materials in architecture, it settles the leakage caused by the direct incorporating the phase change materials, by adopting physical adsorption method to shape the phase change materials. The diffusion-exudation ring tests of the adsorption and setting ability of four carrier materials, such as silica fume, floating bead, activated carbon and silica show that the shape-stabilized phase change material made by physical adsorption method is liquid in macroscopic, but easy to leakage. After encapsulating the phase change material by the gel of silicon and the film coated method respectively, the scanning electron microscope test observing the microscopic appearance of the materials shows that when the carrier is silica, the shape-stabilized phase change material particles distribute envenly, and the pores are encapsulated better. It studies the thermo physical properties of the composite shape-stabilized phase change energy storage materials by differential scanning calorimetry, which demonstrates that the composite shape-stabilized phase change energy storage material with silica made by physical adsorption on the amorphous and gel of silicon performs better, in which the phase change material is 25%, and the phase change enthalpy is 51.21J/g. Compared with the former method, carrier-adsorbed packing method with silica is better, in which the phase change material is 45.5%, and the phase change enthalpy is 80.98J/g. Thus, the latter method is more effective. The performance test of the composite shape-stabilized phase change material in asphalt mixture indicates that the composite shape-stabilized phase change material dose well in low temperature performance and water stable performance of asphalt mixture, and its high-temperature performace meets the current specifications for asphalt pavement performance requirements. Thermostats indoor simulation experiment concludes that the composite shape-stabilized phase change material can reduce heating and cooling rate of asphalt mixsture, and regulate the temperature.