Influence of low-temperature polyurethane solid-solid PCMs particles on the pavement performance of asphalt mixtures

Abstract

In order to slow down the cooling rate of the mixture and reduce the low temperature cracking of asphalt pavement in large temperature difference areas, low-temperature polyurethane solid-solid phase change materials (LPSPCMs) were prepared by prepolymer method. The researches show that LPSPCMs have good phase change heat storage performance and thermal stability performance, and can be applied to hot mix asphalt mixtures. The LPSPCMs particles were incorporated into the asphalt mixture, and the road performance of the LPSPCMs particulate asphalt mixture was tested and analyzed and found: as LPSPCMs particles change the abrasion resistance and embedded effect between asphalt mixes, with the increase of LPSPCMs particles, the high-temperature performance of asphalt mixes first increased and then decreased. The water stability of asphalt mixtures gradually decreases with the increase of LPSPCMs particles content because relative to limestone aggregates, LPSPCMs particles adhere poorly to asphalt. The thermal stress restrained specimen test (TSRST) showed that the cracking temperature of the asphalt mixture gradually decreased with the increase of LPSPCMs particles contents because of the phase change temperature control effect of LPSPCMs particles indicated that LPSPCMs particles improve the low-temperature performance of asphalt mixtures. On this basis, the correlation between the evaluation index of the phase change temperature adjustment effect and the improvement effect of the low-temperature performance of the mixture was established.