What does ASTM C173/C173M refer to?

ASTM C173/C173M specifically refers to the "Standard Test Method for Air Content of Freshly Mixed Concrete by the Volumetric Method." This test method is essential for determining the volume of air present in freshly mixed concrete, which plays a significant role in the concrete's durability and its resistance to freeze-thaw cycles. Accurate measurement of air content is crucial for some types of concrete to ensure proper performance, especially in environments where air voids can help prevent damage from freeze and thaw cycles. The volumetric method allows technicians to obtain a reliable measurement in a straightforward manner, which is vital for quality control in concrete production.

Other options mention various topics related to concrete, but they do not align with ASTM C173/C173M. The focus is strictly on the measurement of air content within freshly mixed concrete, indicating the importance of this aspect in concrete technology and applications.