Resist Chloride Ion Penetration

This test method consists of monitoring the amount of electrical current passed through 2-in. (51-mm) thick slices of 4-in. (102-mm) nominal diameter cores or cylinders during a 6-h period. A potential difference of 60 V dc is maintained across the ends of the specimen, one of which is immersed in a sodium chloride solution, the other in a sodium hydroxide solution. The total charge passed, in coulombs, has been found to be related to the resistance of the specimen to chloride ion penetration.

This test method is applicable to types of concrete where correlations have been established between this test procedure and long term chloride ponding procedures such as those described in AASHTO T 259.

Testing can be done according to the standard methods such as ASTM C 1202, AASHTO T 277 and ASTM C 1760.

Let see hos the test is conducted:

The PROOVE´it system is used to evaluate the resistance of concrete to the ingress of chloride ions in three ways:

1. By determining the total electrical charge that passes through potential across the specimen in accordance with AASHTO T a saturated concrete specimen by applying an electrical 277 or ASTM C1202. This is known as the “Coulomb Test” or electric potential has been applied to the specimen in the “Rapid Chloride Permeability Test (RCPT).”
2. By measuring the penetration depth of chloride ions, after an chloride diffusion coefficient for service life calculations. accordance with Nordtest Build 492 to determine the “Chloride Migration Coefficient,” which can be used to estimate the accordance with ASTM C1760.

3. By measuring the current passing through a saturated concrete specimen and determining the bulk conductivity in accordance with ASTM C1760.

The total charge passed is a measure of the electrical conductance of the concrete during the period of the test or in terms of % of charge resisted through.

As per ASTM C 1202, the results shall be classified as follows:

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