Imaging water ingress into concrete using electrical resistance tomography

This paper investigates the feasibility of imaging the movement of water into partially saturated concrete using electrical resistance tomography (ERT). With this technique, the spatial distribution of electrical resistance within the concrete sample was acquired from 4-point electrical measurements obtained on its surface. As the ingress of water influences the electrical properties of the concrete, it is shown that ERT can assist in monitoring and visualising water movement within concrete. To this end, the difference-imaging technique was used to obtain a qualitative representation of moisture distribution within concrete during the initial 20-hour absorption. It is shown that the technique also enables the influence of surface damage to be studied.