Inner Mongolia Natural Science Foundation of China, No.2019MS05060; Inner Mongolia Higher Education Science Research Project, No.NJZZ20064;
In order to study the influence of DTC phase change material on low-temperature crack resistance and temperature regulation performance of warm mix asphalt mixtures, low-temperature splitting test, temperature stress tests of constrained specimen, nuclear magnetic resonance technology, differential scanning calorimetry were carried out, and the surface temperature of asphalt pavement layers on the test section was measured. The results show that DTC phase change material can achieve heat absorption and release well in the process of rising and cooling. What’s more, it is found that its temperature regulation effect in the cooling process is more obvious by comparing enthalpy values. According to the field temperature measurement, the phase change asphalt pavement is about 6°C higher than that of the ordinary asphalt pavement, and the cooling start time is delayed about 60minutes. However, with the increase of DTC’s dosage, the splitting strength of phase change material asphalt mixture decreases, freeze-off temperature and turning point temperature rise, and the porosity increases, which reduce the low temperature crack resistance of asphalt mixture. The correlation analysis shows that the correlation coefficient of porosity with low temperature splitting strength, freezing break temperature and turning point temperature is above 0.97, and all indexes are closely correlated. Therefore, adding DTC phase change material into asphalt mixture can effectively improve the temperature of asphalt pavement, but it will have a certain negative impact on the anti-crack performance of asphalt pavement. At the same time, Logistic curve fitting of freezing break temperature and turning point temperature was used to obtain the inflection point when DTC dosage was 3‰. Thus, when the DTC dosage is 3‰, the strength of phase change asphalt mixture can not only ensure the specification requirements, only meet the requirements of medium traffic load, but also show stable temperature regulation performance.
宋云连,孙瑜,庞鑫. 冻融条件下相变沥青混合料的低温抗裂及调温性能[J]. 科学技术与工程, 2022, 22(25): 11196-11202.
Song Yunlian, Sun Yun, Pang Xin. Low temperature anti-cracking performance and temperature regulating properties of phase change asphalt mixture under freezing-thawing conditions[J]. Science Technology and Engineering,2022,22(25):11196-11202.