Study of temperature-adjustment asphalt mixtures based on silica-based composite phase change material and its simulation

Abstract

In recent years, extreme temperatures have occurred frequently in summer, which is a challenge to asphalt pavement and its surrounding environment. Phase change materials (PCMs) have unique energy storage characteristics, which provide a new idea for alleviating the high-temperature damage of pavement and reducing the environment temperature. In this paper, the silica composite phase change materials (SiO2-PCMs) were prepared by the sol–gel method, and SiO2-PCMs with better performance was applied to the asphalt mixture. The finite element heat transfer model was established by measuring the boundary conditions, and the temperature adjustment effect was predicted and analyzed. SiO2-PCMs meet the mixing temperature requirements of asphalt mixtures and have excellent compatibility, thermal cycle stability and anti-leakage ability. Asphalt mixture with PEG/SiO2 has an excellent temperature adjustment effect, and it can reduce the upper surface temperature of the asphalt mixture by about 9 °C. The high unity of theory and experiment is implemented by establishing the heat transfer model. PCMs reduce the temperature of asphalt pavement by storing and transforming energy, which provides reference and theoretical support for improving the near-surface thermal environment and prolonging the service life of asphalt pavement.