ABSTRACT

In this paper, based on the Wenner four-electrode principle, an embedded cement-based resistivity sensor was designed to achieve in-situ monitoring of concrete structure durability parameters for structural service life. The sensor was optimized by studying the sensor electrode spacing, and then the effectiveness of the cement-based sensor on the concrete resistivity test was verified by LCR test. On this basis, the effects of concrete cover, water-cement ratio and Chloride ion content on concrete resistivity were discussed, and the correction parameters of in-situ test concrete resistivity were obtained. Furthermore, the investigation on the correlation between concrete resistivity, conductivity and chloride diffusivity was carried out. The results show the conductivity is approximately linear with chloride diffusion coefficient. Finally, an exponential equation that describes resistivity and chloride diffusion coefficient was proposed.