Thermal properties of asphalt concrete: A numerical and experimental study

The aim of this study is to investigate the effects of different design parameters of asphalt concrete and environmental conditions on the thermal properties (thermal conductivity, diffusivity and volumetric heat capacity). A two-dimensional (2-D) numerical model of the asphalt concrete was developed based on the Finite Element Method (FEM). The numerical model was validated by the experimental results using the Transient Plane Source (TPS) method. The experimental results showed that an increase in the ratio of the TPS sensor size to maximum aggregate size improves the accuracy of the thermal properties measurements. A comparison between the thermal properties obtained by the numerical model and the TPS method exhibited a relative error in the range of 2-10%. The numerical model was used to study the effects of the type of aggregates, aggregate gradation, graphite filler in the binder, air void content as well as moisture and freezing conditions on the thermal properties of asphalt concrete. (C) 2017 Elsevier Ltd. All rights reserved.