Surface analyses of bitumen in a context of decarbonation: importance to introduce low frequency dielectric spectroscopy investigation

Non-destructive methods by ground-penetrating radar (GPR) are widely used for road evaluation. To analyze the propagation of electromagnetic waves, it is necessary to have information about the dielectric properties of roads. However, multi-layered structures, various constituents, and a large scale of roads make the direct measurement of core samples hard to be representative. Moreover, climatic conditions will also complicate the analysis due to the dielectric drift. Thus, a non-destructive dielectric measurement adapted for road in situ study is very important. In this work, we will present an open-ended coaxial probe and its application on a newly paved road. In the future, we will integrate the impedance analysis at low frequency to test the dielectric relaxations in different controllable environments, which will help us to better understand the dielectric properties of roads as well as the influences of climate changes.