Which formula represents the calculation for roadway density in asphalt paving?

The formula for calculating roadway density in asphalt paving is based on the relationship between bulk specific gravity (gmb) of the compacted asphalt mix and the maximum specific gravity (gmm) of the asphalt mix. The correct formula, which is represented by the chosen option, reflects this relationship accurately.

In this context, % gmm essentially refers to the percentage of maximum specific gravity that the bulk density of the asphalt mix represents. By using the formula % gmm = (gmb/gmm) x 100, you are effectively measuring how dense the compacted asphalt is in comparison to its maximum potential density. This is crucial for understanding the quality of compaction achieved during the paving process.

The formula demonstrates that if the bulk density increases (meaning more asphalt is compacted into a given volume), the % gmm will also increase, indicating better compaction quality. When using this formula, you'll also see that values are converted into a percentage, which is a common practice in the industry to easily communicate the compaction level.

In summary, this formula accurately captures the method of determining roadway density as it relates the bulk density of the asphalt to its theoretical maximum density, providing insight into the effectiveness of the paving process.