Evaluation of phase change thermoregulated asphalt on low temperature cracking performance of asphalt pavements

The increasing frequency of extreme snowfall in recent years has resulted in widespread road damage, jeopardizing transportation safety and shortening pavement lifespans. While traditional snow removal methods are effective, they often lack environmental sustainability and cost-efficiency. This study addresses this challenge by investigating low-temperature composite phase change microcapsules (LCPCM) for asphalt pavements. These LCPCM harbor tetradecane as the core phase change material and fly ash cenospheres as the carrier. Our study explored their impact on asphalt rheology and freeze-thaw crack resistance. The results show that the LCPCM have good thermal storage and thermal stability, and their enthalpy of phase transition is stable at about 60.42 J/g with a mass loss of only 0.7 %. With the increase of LCPCM doping, the high-temperature rheological rutting factor decreased significantly, while the low-temperature creep rate increased significantly, inhibiting the high-temperature fluidity of asphalt while significantly improving its flexibility. When the dosage of LCPCM reaches 30 %, it effectively improves the thermo-physical properties and low-temperature cracking resistance of asphalt mixtures, and in the outdoor snow melting and ice melting test, the surface ice started to melt 10 minutes in advance. The significant advantages of phase change microcapsules in temperature regulation and snow melting on asphalt pavements were verified from multiple perspectives, providing a new solution for cost reduction and efficiency improvement as well as prolonging the service life of pavements. • LCPCM have good thermal stability and low environmental pollution. • Incorporation of LCPCM has different experimental effects on creep properties of modified asphalt. • LCPCM have a significant effect on improving low-temperature cracking resistance of pavements and delaying pavement ice formation.