This test method covers determination of the air content of freshly mixed concrete from observation of the change in volume of concrete with a change in pressure. ASTM C231 is intended for use with concretes and mortars made with relatively dense aggregates for which the aggregate correction factor can be satisfactorily determined by the technique. It is not applicable to concretes made with lightweight aggregates, air-cooled blast-furnace slag, or aggregates of high porosity. This test method is also not applicable to nonplastic concrete such as is commonly used in the manufacture of pipe and concrete masonry units.
KeywordsC231 - Air Content - Correction Factor - Freshly Mixed Concrete - Pressure - Volume
ICS CODEICS Number Code 91.100.30 (Concrete and concrete products)
ASTM C231 / C231M-17a, Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method, ASTM International, West Conshohocken, PA, 2017, www.astm.org