Measurement of Electrical Conductivity and Detection of Water in Concrete with CFGFRP Used as Electrodes

The water content in cement mortar and flowing water in concrete were measured with CFGFRP (carbon fiber-glass fiber-reinforced plastics) composites used as electrodes. The electrical resistance and conductivity of cement mortar and concrete were influenced by frequency, applied voltage and temperature. The frequency of 1kHz and applied voltage of 5V were used for measuring in the present study. The conductivity of cement mortar decreased with decreasing water content. The conductivity of cement mortar and concrete increased in short time with adsorbing or flowing water. CFGFRP composites are promising as electrode of intelligent concrete structures measuring both water content and flowing water.