Phase Change Heat-induced Structure of Asphalt Pavement for Reducing the Pavement Temperature

Composite-shaped phase change materials (CS-PCMs) regulate temperature by storing and releasing heat energy during a phase transition. High/low thermal conductivity materials can change temperature by transferring/blocking heat. To cool the asphalt pavement, alleviate rutting damage, and improve the urban heat island effect, heat transfer models and rutting models were established based on the finite element software ABAQUS, and different CS-PCMs and thermally conductive materials were selected according to the different temperatures and heat flux densities of each surface layer. A phase change-heat-induced structure (PC-HIS) was designed through the combination of phase transition heat storage and heat induction, and a blank structure (BS), phase change structure (PCS) with only phase change added, and heat-induced structure (HIS) with only thermal conductivity added were set as the control group. The results of the heat transfer models showed that, compared with a BS, the maximum simulated temperatures of the PC-HIS, PCS, and HIS decreased by 3.7 ℃, 2.2 ℃, and 3.0 ℃, respectively. The downward heat conduction rates at 18 cm decreased by 9.2%, 4.8%, and 3.5%, which showed that the PC-HIS is more effective than other structures in reducing temperature and preventing downward heat. The simulation results agree well with the indoor irradiation test results. The rutting quantitative analysis results showed that the maximum rutting depths of the PC-HIS, PCS, and HIS were reduced by 53.5%, 44.2%, and 16.3%, respectively. The PC-HIS is expected to be used to cool the pavement and resist rutting.