AASHTO T 260-21 PDF Download

AASHTO T 260-21 is a standard method of testing and sampling for chloride ion in concrete and concrete raw materials. This standard provides procedures for determining the acid-soluble chloride ion content or the water-soluble chloride ion content in aggregates, portland cement, mortar, or concrete.

The acid-soluble chloride ion content is typically equal to the total amount of chloride present. However, certain organic additives or minerals with acid-insoluble chloride might be present in concrete or concrete raw materials. These constituents can become acid soluble over time when exposed to the alkaline environment in concrete or mortar.

The water-soluble chloride ion content can be affected by the age of the concrete, mortar, or hydrated portland cement at the time of sampling. To ensure accurate results, it is recommended that the material is well-cured and at least 28 days old before sampling, unless early age studies are specifically desired.