Multiphase Dielectric Mixing Model for Concrete Mixtures

Abstract

The advancement of high-power microwave technology has indeed brought about the possibility of E-bombs, also known as electromagnetic pulse (EMP) bombs. These weapons emit an electromagnetic pulse that can disable electrical circuitry within a specific radius. As the frequency spectrum becomes more congested with various technologies operating in similar frequency bands, the need for shielding against interference becomes crucial. One promising solution is the use of conductive concrete, which is created by incorporating conductive components into a traditional concrete mixture. This conductive concrete has shown excellent shielding properties and improved electrical characteristics. To assess and quantify its effectiveness, the relative complex permittivity of the concrete mixture needs to be estimated. In this paper, the authors propose a method for estimating the relative complex permittivity of the concrete mixture. This was achieved by measuring the scattering parameters of concrete samples using a rectangular waveguide within the C-band frequency range. The scattering parameters provide valuable information about how electromagnetic waves interact with the concrete. A dielectric mixing model was developed to determine the relative complex permittivity. This model takes into account the volume percentage and the dielectric properties of the individual constituents present in the concrete mixture. By applying this model and obtaining the complex permittivity of the mixture, it becomes possible to calculate the required thickness of the conductive concrete mix needed to achieve the desired levels of electromagnetic attenuation and shielding.