Resistance measurements of high resistance concrete
Abstract
The importance of concrete resistivity in durability and service life aspects is widely recognized. Within this project, different measurement approaches were evaluated, with associated limitations and advantages. The resistivity of high resistance concrete samples at different storing conditions was investigated. The samples were tested with and LCR meter and Electrical Impedance Spectroscopy (EIS), sweeping a large frequency range.The results confirm that the chosen electrode contact solutions and the samples storage conditions influence on the measured resistance, including the ohmic measuring frequency. Furthermore, it was found that for samples with low moisture content, frequencies below the recommended range (50 Hz to 100 Hz) must be applied to obtain the actual/real ohmic resistance. The results obtained by EIS were compared to measurements from a LCR meter. The comparison demonstrates that the actual ohmic resistance (from EIS) and the one measured with an LCR show good agreement when information about the phase angle (angle between current and voltage) is considered.