Significance and Use

This test method is applicable to cementitious mixtures that have not been exposed to external chloride ions, other than the negligible quantity of chloride ion exposure from sample preparation using potable water, prior to the test.

The calculation procedure described in this test method is applicable only to laboratory test specimens exposed to a sodium chloride solution as described in this test method. This calculation procedure is not applicable to specimens exposed to chloride ions during cyclic wetting and drying.

Note 1The diffusion of ionic species in concrete occurs within the fluid-filled pores, cracks and void spaces. The concentration and valence of other ionic species in the pore fluid also influence the rate of chloride diffusion, and therefore, the apparent diffusion coefficient as determined by this test procedure.

In most cases, the value of the apparent chloride diffusion coefficient for cementitious mixtures changes over time (See Note 2). Therefore, apparent diffusion coefficients obtained at early ages may not be representative of performance in service.

Note 2The rate of change of the apparent diffusion coefficient for cementitious mixtures containing pozzolans or blast-furnace slag is typically different than that for mixtures containing only portland cement.

The apparent chloride diffusion coefficient is used in Fick's second law of diffusion to estimate chloride penetration into cementitious mixtures that are in a saturated condition.

The apparent chloride diffusion coefficient is commonly used in chloride ingress models based on Fick's second law of diffusion. The apparent diffusion coefficient determined by this method includes bound chloride, so proper use of the apparent chloride diffusion coefficient to predict chloride ingress requires consideration of chloride binding.

The resistance to chloride penetration is affected by such factors as the environment, finishing, mixture composition, workmanship, curing, and age.

1. Scope

1.1 This test method covers the laboratory determination of the apparent chloride diffusion coefficient for hardened cementitious mixtures.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

C31/C31M Practice for Making and Curing Concrete Test Specimens in the Field

C42/C42M Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete

C125 Terminology Relating to Concrete and Concrete Aggregates

C192/C192M Practice for Making and Curing Concrete Test Specimens in the Laboratory

C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials

C1152/C1152M Test Method for Acid-Soluble Chloride in Mortar and Concrete

C1202 Test Method for Electrical Indication of Concretes Ability to Resist Chloride Ion Penetration

NORDTEST Standards

Keywords

chloride; concrete; corrosion; diffusion; ion transport; service life; Apparent chloride diffusion coefficient; Chloride analysis--concrete/aggregate; Chloride diffusion coefficient; Corrosion--concrete; Diffusion; Hardened cementitious mixtures; Ion transport; Laboratory analysis/evaluation; Service life processing/analysis

ICS Code

ICS Number Code 71.060.99 (Other inorganic chemicals)

DOI: 10.1520/C1556-11A

ASTM International is a member of CrossRef.

ASTM C1556