Experimental Characteristic Of Heat Conduction Of Aggregates Treated By Cement

In order to deeply understand pavement temperature field and its thermodynamics characteristics, it is necessary to analyze the thermal conductivity of the pavement materials. At present, there are many researches on the thermal conductivity of asphalt mixture, while few people pay attention to the thermal conductivity of cement treated aggregate mixture, which is also a common used pavement material. Taking the structure characteristic of an accumulation materials in great volume into account, an experimental device in type of double plane samples for heat conduction applying the Fourier’s Law is used in this paper. Considering the temperature field and structure of asphalt pavement for the supporting project, different kinds of cement treated aggregate mixture in three different cement contents are studied to measure the heat conductivity in different test temperature between-5℃~45℃.The main conclusion are as follows: The heat conductivity of cement stabilized macadam mixture is a temperature changing value which means that it will increase as the heating temperature increase. When the range of test temperature is-5 ℃ to 45 ℃, the thermal conductivity coefficient ranges from 1.03W/(m·k) to 1.60W/(m·k). Under the same test temperature, the thermal conductivity of suspend-dense mixtures is greater than that of skeleton dense structure, which means the cement treated aggregate mixture of dense structure has a great heat conduction performance. When the cement content is small, the thermal conductivity of cement treated base material is small, and when the cement content reaches a certain level, there is little difference between the thermal conductivities of cement treated base materials of different cement contents. As a result, the first factor influencing the heat conductivity is the structure type, while the second is the cement content. On the basis of the heat conduction test, there is an analysis on the pavement temperature field for the supporting project, and the research implies that pavement heat conduction is usually in transient state but not in steady state and different thermal conductivity may change the pavement temperature field.