Electromagnetic properties of concrete: bottom-up modeling from the molecular scale

The electromagnetic response of concrete can be used to the non-destructive testing of structures and to follow early-age property development. Fundamental understanding of the physical origins of the electromagnetic response of cement-based materials is critical to reduce the empirism in the interpretation of electromagnetic-based techniques. The pore solution is the main contribution to the electrical conductivity and dielectric response of porous geomaterials. Specific ion effects are known to impact the dynamics of ions in aqueous salt solutions. In this context, molecular dynamics (MD) simulation is a well-suited technique to compute and understand how the ionic composition of the pore solution affects the electromagnetic properties of concrete. Here, we discuss recent results of MD simulation on bulk solution mimicking concrete pore solution. Then, we upscale the information from the molecular scale up to the concrete scale in order to provide a multiscale model of the electrical conductivity and frequency-dependent dielectric response of cement-based materials.