Concrete Moisture Content Measurement Using Interdigitated Near-Field Sensors

The efficacy of a meander and a circular interdigitated sensor in detecting and measuring the moisture present in wet concrete samples is demonstrated. Analytical, simulation, and measurement results of interelectrode capacitance for samples with different moisture contents show good agreement. As moisture content increases from 0% to 6%, the interelectrode capacitance that predicts the moisture content increases by 126.4% for the meander sensor and 187% for the circular sensor. Regression analysis of the measured data demonstrates that for moisture content less than 6% the relationship between the measured capacitance and the percent moisture content is predominantly linear.