Dielectric permittivity of C-S-H

SA Hamadouche and T Honorio and T Bore and F Benboudjema and F Daout and E Vourch, CEMENT AND CONCRETE RESEARCH, 169, 107178 (2023).

DOI: 10.1016/j.cemconres.2023.107178

As a porous hydrophilic phase, C-S-H is expected to exhibit a frequency- dependent dielectric response. This C- S-H property remains unknown, despite the importance of dielectric assessment for non-destructive evaluation of concrete. This study adopts a multiscale approach to estimate the complex dielectric response of C-S-H over the 0 to 1000 GHz frequency range. We perform molecular dynamics simulations to compute the frequency -dependent dielectric response of water in C-S-H from the polarization correlation formula. We consider pore sizes covering the range associated with interlayer and gel pores in C-S-H. The dielectric response obtained is anisotropic and pore size dependent, as expected in layered materials. The results at the molecular scale are then used as inputs in a homogenization model to estimate the dielectric permittivity of C-S-H gel, which we compare with estimations obtained from inverse analysis based on experiments. Our results are a valuable input for multiscale modeling of non-destructive testing and evaluation in cement- based materials.

Return to Publications page