Title: Electrical Tests for Concrete Penetrability, Part 2
Author(s): Karthik H. Obla and Colin L. Lobo
Publication: Materials Journal
Appears on pages(s): 55-64
Keywords: chloride; curing; degree of saturation; leaching; penetrability; pore solution; rapid chloride permeability (RCP); resistivity; transport
The resistivity of concrete is evolving as a reliable method to measure the penetrability of water and dissolved chemicals into concrete. In Part 1 of this two-part paper, the results of the bulk and surface resistivity of specimens conditioned by different methods were compared to the results of chloride ion penetrability by ASTM C1202, and the precision of test determinations was reported. In Part 2, the results illustrate how changing the specimen conditioning method can change how concrete mixtures are characterized for chloride ion penetrability or transport properties. For the different mixtures evaluated, specimens subjected to the same curing condition had different degrees of saturation levels at the end of the conditioning period. Correcting the measured resistivity for degree of saturation, however, led to inaccurate mixture classification. The paper recommends a preferred specimen conditioning method for the resistivity test.