AS 1012.20.1:2016 PDF Download

AS 1012.20.1:2016 standard outlines the procedure for detecting chlorides and sulfates in hardened concrete, mortar, grout, and concrete aggregates. The method described in this standard involves extracting the material using nitric acid, rather than boiling water, and using a finer fraction of material passing through a 150µm sieve.

One significant difference between this method and AS 1012.20.2 is that the nitric acid extraction method dissolves easily oxidizable sulfides, which are then reported as sulfates. Additionally, to ensure compliance with the relevant requirements specified in AS 3600 and AS 5100, additional tests and calculations may be necessary.

The standard also provides some important notes. One note emphasizes the availability of separate test methods for analyzing other concrete-making materials, such as cementitious materials, admixtures, and water. Another note highlights the significance of sampling technique, as there can be gross variations in chloride and sulfate contents even within a few millimeters. Factors such as leaching, surface evaporation, crusting, and penetration of salt and ground waters can contribute to these variations. It is also recommended to restrict the amount of water used during coring, especially for small diameter cores. Additionally, the solutions obtained from this method can be used to determine the acid-soluble calcium oxide content of the materials.