What does absorption refer to in the context of aggregates?

• A. The weight of dry aggregate
• B. The weight of aggregate after washing
• C. The increase in weight of aggregate due to absorption of water
• D. The decrease in weight of aggregate due to evaporation

Answer: (C)

Absorption in the context of aggregates refers specifically to the increase in weight of aggregate due to the absorption of water. When aggregates are exposed to water, they can absorb moisture through their porous surfaces. This absorbed water adds to the overall weight of the aggregate, which is critical for understanding how aggregates behave in concrete mixtures and other applications.

The concept of absorption is important for ensuring the right mix ratios in concrete, as it influences the amount of water needed to achieve the desired workability and strength. Knowing the absorption characteristics helps in predicting how much water will be taken up by the aggregates and ensures that the concrete performs as expected.

In contrast, measuring the weight of dry aggregate, the weight after washing, or the weight loss due to evaporation does not directly address the process of absorption itself.