scope:

Describes a test method for determination of the air-void structure in a hardened concrete sample which contains entrained air. The air-void structure is described by means of the following parameters, which are defined in clause 3. I) Total air content II) Specific surface of air void system III) Spacing factor IV) Air-void size distribution V) Micro air content. The method as described is only suitable for use on hardened concrete specimens where the original mix proportions of the concrete are accurately known and the specimen is representative of these mix proportions. This will generally be the case only where the concrete concerned is produced in a laboratory.