When is a moisture content sample considered dry?

A moisture content sample is considered dry when it shows less than 0.1% additional loss after further heating. This criterion is crucial because it indicates that most, if not all, of the water that could have been evaporated from the sample has already been removed.

In soil and aggregate testing, moisture content is an important factor that can significantly affect the material's properties and behavior. The method of determining the moisture content typically involves drying the sample in an oven and measuring the weight loss. If a subsequent heating does not result in weight loss beyond 0.1%, it suggests that the sample has reached a sufficient state of dryness, meaning it no longer contains a significant amount of moisture that could affect test results.

While other options may seem relevant, they do not provide a definitive measure of dryness. Simply being heated for a certain time or cooling to room temperature does not guarantee that all moisture has been removed. Similarly, the absence of visible moisture does not conclusively indicate that the material is free from moisture at a microscopic level, which can still impact the final results when assessing soil and aggregate properties. Thus, the threshold of less than 0.1% additional weight loss is an established and rigorous criterion for determining when a moisture content sample