ASTM C173/C173M-16 PDF Download

ASTM C173/ C173M-16 is a standard test method that determines the air content of freshly mixed concrete by the volumetric method. The test measures the air contained in the mortar fraction of the concrete, excluding any air present inside porous aggregate particles. This makes it suitable for determining the air content of concretes with lightweight aggregates, air-cooled slag, and highly porous or vesicular natural aggregates.

The test method requires the addition of isopropyl alcohol to the water used to fill the meter. The goal is to minimize or eliminate the collection of foam in the neck of the top section of the meter during rolling. If more than 2% of air equivalent foam is present, the test is considered invalid and must be repeated with a greater quantity of alcohol. It is not allowed to add alcohol after the initial filling of the meter to the zero mark.

It is important to note that the air content of hardened concrete may differ from what is determined by this test method. Variation may be influenced by factors such as the consolidation effort applied to the concrete, stability of air bubbles, accuracy of microscopic examination, time of comparison, environmental exposure, and the stage in the delivery, placement, and consolidation processes at which the air content is determined.