Study on the Thermoregulation Mechanism of Temperature Insensitive Asphalt Pavement

Incorporating phase change materials into asphalt concrete and utilizing phase change heat transfer to control the temperature of asphalt pavement can effectively reduce the impact of high temperatures on the durability of asphalt pavement. In this study, microencapsulated composite phase change materials were prepared using calcium alginate and polyethylene glycol (PEG) 1500 and mixed into SMA-13 Marshall specimens for indoor high-temperature tests. The test results show that the temperature of the specimen was reduced by about 1.5 °C when the doping amount of the composite phase change material was 2.4% and the oven temperature was 60 °C. In order to further investigate the application of phase change energy storage materials in asphalt pavement structure, this study used Comsol finite element software to simulate the summer temperature field of the asphalt surface layer. A three-layer asphalt pavement model consisting of 4 cm SMA-13, 6 cm AC-20, and 8 cm AC-25 was established to study the effect of phase change materials on the temperature change in the pavement. The results of this study show that adding 2.4% of the composite phase change material to each of the top and middle surface layers kept the temperature of all pavement layers outside of the temperature range in which the asphalt's dynamic stability plunges.