Thermophysical Properties And Test Of Asphalt And Asphalt Mixture

Thermal properties is basic nature of asphalt and asphalt mixtures,which decided asphalt and asphalt thermal properties, thermal response, etc., especially thermal parameter is basic parameter to study the pavement temperature, accuracy of thermal parameter has a significant impact on temperature distribution. Throughout the study abroad situation, given parameter values of asphalt and asphalt mixtures are not the same by different researchers, there is a big numerical difference, and not get more exact and reasonable thermal conductivity derived formula. So far, the thermal properties of asphalt mixture parameters obtained mostly through experimental testing, as test equipment, test conditions, test personnel can't rule out the possibility of random constraints and impact, making the test results vary widely. Therefore, proposed a more Sensible thermal parameters of asphalt mixture testing is particularly important.In this paper, the heat flow of asphalt and asphalt mixture with temperature variation was studied by DSC. According the principle of DSC, setting the temperature scanning range of -30 ~ 180℃, scanning frequency of 10℃/ min scanned the temperature of asphalt, modified asphalt, limestone gravel, limestone powder, basalt stones, basalt stone, granite stone, granite powder and wrapped in limestone gravel covered asphalt, granite stone wrapped covered asphalt, basalt stones wrapped cover asphalt. We obtained the Specific heat test values of their by Using DSC test and calculation software. Through multiple parallel test of asphalt, modified asphalt, granite, limestone, basalt ,got their range of test data and geometric mean, and discussed the data dispersion and factors of asphalt, stone thermal parameters and experimental by DSC tests.Based on the testing principle of the unsteady conduction cooling method model and the infinite model, we design a simple mixture indoor thermal diffusivity testing device to test thermal conductivity of asphalt mixture, used the two models calculated thermal conductivity of asphalt mixtures, and compared the two calculation methods. Different porosity by thermal conductivity test specimens of different porosity on thermal diffusivity and calculated parameters.According to specific heat increases Principle of mixtures, calculated specific heat of asphalt mixture using the measured specific heat of asphalt and gravel, and compared with the measured value.According to the conversion relationships between specific heat, thermal conductivity, and thermal coefficient, calculated thermal conductivity of asphalt mixture of the use of by measured thermal diffusivity and calculation and measured value of specific heat. Research results have been compared with that calculated the specific heat thermal conductivity of domestic and foreign research results are closer. Given the thermal test difficulty, this article suggests testing separately the specific heat of asphalt and gravel, and then getting the specific heat of asphalt mixture by the principle of specific heat increases, and specific heat estimation formula of asphalt mixtures are given.This paper provides a new reference method for thermal properties research on asphalt and asphalt mixture, discussed the feasibility of derived thermal parameters of asphalt mixture by Component Parameters derived from material. This study provides a new idea for the follow-up.