A blank sample of aggregate (without asphalt binder) is prepared during the correction factor sample preparation to provide a comparison of the gradation with the mixture (burned) samples later.

• A. False
• B. Only used for gradation of burned samples
• C. True
• D. It is optional

Answer: (C)

In this part of the testing process, you create a blank sample of aggregate without binder so you have a baseline for the aggregate’s gradation. This baseline is then used to compare against the gradation of samples where the asphalt binder has been burned off. By comparing the bare-aggregate gradation with the burned samples, you can see how the ignition process affects particle sizes and determine the correction factor needed to adjust the final gradation of the mixture. So the statement is true: a blank aggregate sample is prepared for this comparison. It’s not limited to burned samples and it isn’t optional, because this blank provides the essential reference needed to accurately assess changes in gradation during correction factor analysis.