Experimental study on thermophysical properties of HMA during compaction

The thermal parameters are key parameters for evaluating the temperature field and temperature stress of asphalt pavement. However, due to the restriction of tradition test method, the thermal parameters of asphalt and asphalt mixtures measured by various researchers are quite different. Therefore, it is particularly important to introduce a simple and standard test method for thermal parameters of asphalt mixtures. This research proposed a novel test method to precisely determine the thermal parameters of asphalt mixture during compaction temperature, the effects of different air voids on the thermal diffusivity and parameters were evaluated. Differential scanning calorimetry (DSC) was used to measure the heat flow curves of asphalt and asphalt mixture, and the calculated and measured specific heat values of the mixture were obtained. Then the corresponding thermal conductivity was calculated from the conversion relationship between thermal parameters. The results indicated that the thermal conductivity converted from the calculated value of specific heat is close to previous studies, but the thermal parameters of the temperature field during the compaction process can be obtained accurately and conveniently. This research provides a new method for the thermal properties evaluation of asphalt and asphalt mixture .