An analytical model for determining the relative electrical resistivity of cement paste and C-S-H gel

With a combination of effective medium and percolation theory, an analytical model was proposed to acquire the relative resistivity of cement paste and C-S-H. The overall electrical resistivity and volume fraction of conductive phase, as main input values, are continuously determined by using non-contact electrical resistivity device and CEMHYD3D numerical model, respectively. The results show that an increase of hydration degree shows an improvement with the relative resistivity of solids and a reduction in critical exponent of capillary pores. While the relative resistivity of C-S-H and its exponent present constant values of 121 and 1.8, independent of hydration degree. Finally, the calculated results are compared to the reported values by previous literatures that have a good agreement.