Temperature-regulating asphalt mixture incorporating phase change and high-reflective materials: Thermal behavior and mechanical performance

Extreme seasonal temperature fluctuations pose substantial challenges to asphalt pavement performance, particularly under intense summer heat and winter freeze–thaw cycles. This study compares the effects of individual and combined use of phase change materials (PCM) and high-reflectivity materials (HRM) on asphalt properties, while also investigating the effects of dry and wet incorporation of HRM and the dry incorporation of PCM to determine the most effective incorporation method. A series of laboratory experiments were conducted to evaluate the mechanical and thermal regulation performance of the mixtures. Mechanical characterization included Marshall stability, dynamic modulus, uniaxial creep, and moisture stability tests, providing a comprehensive assessment of structural behavior. Thermal regulation performance is examined through environmental simulations designed to replicate seasonal environmental conditions, such as solar heating to simulate high summer temperatures, laboratory freezing to reproduce winter freeze conditions, and low-temperature ice-pulling tests. Results show that HRM enhances high-temperature stability and stiffness, while PCM improves low-temperature ductility and resistance to freeze–thaw damage. The dual-modified mixtures maintain structural integrity while offering improved mechanical balance. In terms of thermal regulation, HRM effectively reduces asphalt surface temperatures by up to 5–6 °C under solar exposure, particularly when applied via wet mixing, which improves material dispersion and integration. PCM demonstrates strong self-deicing potential by delaying freezing onset and weakening ice adhesion through latent heat release. The combined use of HRM and PCM achieves complementary thermal control effects in both summer and winter scenarios. In particular, wet mixing ensures better material dispersion and interfacial bonding, resulting in more stable temperature regulation and enhanced mechanical performance compared to dry mixing. This study provides new insights into the synergistic design of thermally adaptive asphalt mixtures, offering methodological reference for developing climate-resilient pavements. • HRM reduces the temperature of asphalt mixture when exposed to high temperatures. • PCM delays the freezing of asphalt mixtures and improves their ice-breaking performance. • Compared to dry mixing, wet mixing ensures better temperature control and road performance of the mixture. • The combined use of HRM and PCM achieves bidirectional temperature regulation of asphalt mixtures.