Title:
Fly Ash Concrete: An Evaluation Of Chloride Penetration Testing Methods
Author(s):
John M. Scanton, Matthew R. Sherman
Publication:
Concrete International
Volume:
18
Issue:
6
Appears on pages(s):
57-62
Keywords:
DOI:
Date:
6/1/1996
Abstract:
When the AASHTO T277 rapid permeability coulomb test became popular as a means of evaluating the relative permeability of concrete, concrete containing fly ash performed poorly compared to concrete containing other materials. This was the case when this electrical indication test was the sole method used, rather than by actual chloride penetration over time. After reviewing the literature, Wiss, Janney, Elstner Associates, Inc. (WJE), recognized these indications of inconsistent test results in a published article. WJE performed various tests to verify the ability of fly ash to improve the chloride penetration resistance of concrete. The primary tests performed on a reference portland cement concrete and various concretes containing fly ash and silica fume were: - apparent rapid chloride permeability, - actual chloride ion penetration (ponding), and - time to corrosion, ASTM G 109. This paper verifies that concrete containing fly ash is very resistant to chloride penetration, and that the rapid chloride test can be used, but that the results have to be correlated with the AASHTO T259 chloride ponding test.