How does air entrainment help concrete?

Air entrainment plays a crucial role in enhancing the durability of concrete, particularly in environments subjected to freeze-thaw cycles. When air-entraining agents are added to the concrete mix, tiny air bubbles are created. These bubbles provide space for water to expand when it freezes, thereby reducing the risk of cracking and spalling that can occur if water inside the concrete expands during freezing.

In addition to improving frost resistance, air entrainment also helps minimize segregation, which refers to the separation of coarse aggregates from the concrete matrix. By maintaining a more uniform distribution of aggregates, the concrete can achieve better strength and performance characteristics.

Factors like workability, color consistency, and cost are not directly influenced by the primary purpose of air entrainment, which is to confer durability benefits. Therefore, the assertion that air entrainment increases durability by improving frost resistance and reducing segregation is indeed accurate.