The dielectric response of hydrating porous cement paste

Abstract

The dielectric response of hydrating cement paste has been measured in the frequency range 5 - Hz. The spectra of complex capacitance have been characterized in terms of the dispersive bulk and barrier responses at high- and low-frequency ranges, respectively, and by a generalized Maxwell - Wagner response at intermediate frequencies. We have developed a theoretical model for the bulk response of the cement paste by considering a lattice gas model for the diffusion of ions in pores exhibiting a fractal distribution in size. Using this model we have assigned physical meanings to parameters characterizing the bulk dielectric response and have determined the variation of these parameters during hydration.