Determination of water content for early-age concrete based on dielectric constant

A new model for determining the water content of early-age concrete is proposed in this paper. The water-cement (w/c) ratios of early-age concrete can be determined based on the measured dielectric constant. The experimental results show that the relation between the relative dielectric constant (ϵr') and w/c can be modelled by a linear function at microwave frequency of 2 GHz. The model has verified and shown to have good repeatability and, hence, can be used to monitor the concrete curing and structural health conditions