Discretized conductivity measurements to study wetting and drying of cover zone concrete

In situ electrical measurements are used in conjunction with surface-applied, volumetric gain methods to study cover zone concrete under a wetting and drying regime. Ordinary Portland cement (OPC) concretes and OPC with partial replacement with ground granulated blast-furnace slag were used in the experimental programme with samples exposed to water and chloride solution. Monitoring the variation of electrical properties at discrete points within the surface 50 mm, during absorption and after drying, provides information on water and ionic penetration into the cover zone; drying response, and evidence of continuing hydrationlchloride-binding effects.