Title: Electrical Tests for Concrete Penetrability, Part 1
Author(s): Karthik H. Obla and Colin L. Lobo
Publication: Materials Journal
Appears on pages(s): 45-54
Keywords: chloride; condition; curing; penetrability; pore solution; rapid chloride permeability (RCP); resistivity; transport
The resistivity of concrete is gaining acceptance as an easier and more reliable method to measure the penetrability of water and dissolved chemicals into concrete. This study evaluates the surface and bulk resistivity of concrete specimens prepared from mixtures with varying levels of penetrability or transport properties. Test specimens were conditioned by different methods as permitted by the standards. In Part 1, the results indicate that, based on measured resistivity, concrete mixtures are classified for transport properties similar to ASTM C1202. Resistivity measurements were less variable. Changes in the resistivity of specimens placed in simulated
service conditions for 1 year are also evaluated. Comparisons were also made on resistivity measured on smaller specimens obtained from different locations of a cylindrical specimen. In Part 2, the impact of various specimen conditioning techniques allowed by the standards on the degree of saturation, resistivity, and characterization of concrete for transport properties are discussed.