Regulating porous asphalt concrete temperature using PEG/SiO2 phase change composite: Experiment and simulation

Abstract

Open-graded friction course (OGFC) is prone to deformation-related clogging during summer owing to high internal temperature. Reducing OGFC temperature during summer has significant benefits in relation to mitigation of rutting and clogging problems. A phase change composite material with PEG-4000 serving as the core and SiO2 as the shell (PEG/SiO2) was used to modify OGFC. Different mechanical performance tests were conducted, and the results showed that the addition of the PEG/SiO2 only has slight negative impacts. The effectiveness of the PEG/SiO2 modified OGFC for pavement temperature regulation was subsequently demonstrated through a lab-scale, indoor heating test using slab specimens with different PEG/SiO2 dosages and moisture conditions. Finally, a 3-D heat transfer modeling technique was applied to model the temperature field of the slab during the heating test. The results from the numerical simulation were generally in close agreement with the lab test results. Based on this study, using PEG/SiO2 phase change composite to modify OGFC can be considered as an effective approach to reducing porous pavement temperature during summer.