Novel Computational Method for Determination of Thermal Conductivity of Pavement Materials

Knowledge of temperature distribution within a pavement structure is essential for thermal stability analysis of asphalt pavement materials and thermal environment studies of urban built-up areas. Thermal conductivity of pavement materials is required for both types of analyses. However, many pavement engineering laboratories lack the necessary equipment to test thermal conductivity, which can be tedious and time-consuming. To address this issue, the present study introduces a novel numerical procedure that determines the thermal conductivity of asphalt pavement materials. This approach applies the finite element method using the traditional row- and-column finite element mesh to represent a typical asphalt mixture consisting of the following constituents: asphalt binder, mineral aggregates, air, and moisture (if present). The accuracy of two- and three-dimensional finite element simulation models is presented and compared. The 2D model underestimates k by up to 5.01% when using the 3D anticipated value as a baseline. When high accuracy is not required, a two-dimensional model can also be used to predict the thermal conductivity of asphalt mixtures.