Fabrication of cooling asphalt pavement by novel material and its thermodynamics model

Abstract

It is an important research field to restrict the extreme temperature of pavement by using the robust thermal performance of phase change materials. In this study, diatomite, expanded perlite, and stearic acid were chosen to prepare compound phase change materials (CPCMs) for the fabrication of novel cooling asphalt pavement. The microtopography and characteristics of CPCMs were described by scanning electronic micro-scopy, Fourier transform infrared spectroscopy and X-ray diffraction. The thermal performance and stability were confirmed by thermogravimetric analysis and differential scanning calorimetry. The cooling asphalt pavement was evaluated by pavement performance and thermal performance test. Finally, the heat transfer simulation of the cooling asphalt pavement and the conventional asphalt pavement were established by the finite element method. CPCMs with diatomite as carrier still feature superior chemical and thermal stability after 100 cycles. The upper and bottom surface temperatures of the asphalt pavement can be reduced by 10.90 °C and 5.03 °C, respectively. The temperature gradient at each stage showed that the addition of CPCMs helps to restrict the extreme temperature of the pavement, and has the potential to restrict the temperature extremities in pavement and the effect of urban heat island.