How is the absorption capacity of aggregates determined?

The absorption capacity of aggregates is determined by weighing the dry aggregate and then soaking it in water. This method allows for a direct measurement of how much moisture the aggregate can absorb, which is critical for understanding how it will behave in concrete or other mixtures.

When the dry aggregate is weighed initially, it provides a baseline weight. After being soaked, the aggregate will have absorbed water, increasing its weight. The difference in weight before and after soaking is used to calculate the absorption capacity. This percentage is important for mix design because aggregates with higher absorption capacities can lead to changes in water-cement ratios and affect the overall quality and durability of the concrete.

The other methods mentioned are not suitable for determining absorption capacity. Soaking the aggregate in oil would not provide relevant information about water absorption. Heating the aggregate to measure evaporation could show moisture loss but does not specifically indicate how much water the aggregate can retain. Visually inspecting aggregates for cracks could give insight into their structural integrity but does not relate to their ability to absorb water.