Which statement best describes absorption in materials like concrete?

Which statement best describes absorption in materials like concrete?

• A. The process by which a material takes in moisture, increasing its weight, typically expressed as a percentage of the dry weight.
• B. Moisture that is permanently bonded to aggregate surfaces.
• C. The process of releasing absorbed water during curing.
• D. The total moisture content including free water and bound water.

Answer: (A)

Absorption is about how much moisture a material can take into its pores, which makes the material heavier. In concrete, this is expressed as the percentage increase in weight compared to the dry weight. This specific measure focuses on water that has entered the material, not the total water already present. The best choice says the material takes in moisture, increasing its weight, and is expressed as a percentage of the dry weight. That captures the essence of absorption as a quantifiable gain in weight due to water entry. The other options mix up related concepts: moisture permanently bonded to surfaces describes adsorption, not absorption; releasing absorbed water during curing refers to desorption or drying, the opposite of absorption; and total moisture content includes all water in the material (both free and bound), not the uptake process measured as weight gain relative to dry weight.

Absorption is about how much moisture a material can take into its pores, which makes the material heavier. In concrete, this is expressed as the percentage increase in weight compared to the dry weight. This specific measure focuses on water that has entered the material, not the total water already present.

The best choice says the material takes in moisture, increasing its weight, and is expressed as a percentage of the dry weight. That captures the essence of absorption as a quantifiable gain in weight due to water entry.

The other options mix up related concepts: moisture permanently bonded to surfaces describes adsorption, not absorption; releasing absorbed water during curing refers to desorption or drying, the opposite of absorption; and total moisture content includes all water in the material (both free and bound), not the uptake process measured as weight gain relative to dry weight.