At what temperature and for how long must GMB and GMM samples be conditioned?

The correct answer emphasizes the specific conditions necessary for accurately conditioning GMB (Bulk Specific Gravity of a material) and GMM (Maximum Specific Gravity of a material) samples. The conditioning temperature is critical because it ensures that the samples reach a consistent state representative of their behavior during production.

In this case, conditioning at a temperature that is plus or minus 9° around the compaction temperature is ideal, as it strikes a balance that minimizes the risk of either underheating or overheating the sample, which could affect the measurements.

Conditioning for a duration of 1 hour with a tolerance of +/- 5 minutes is also important to ensure that the samples have sufficient time to adjust to the target temperature. This exact timing ensures results that are precise and repeatable, which are essential in quality control in asphalt production.

Overall, these specifications help produce reliable data for testing, aiming for consistency in the performance of asphalt mixtures.