To determine a target asphalt spread rate for non FC-5 mixes, what is the formula used?

The correct formula for determining a target asphalt spread rate for non FC-5 mixes involves using the specific gravity of the mix, denoted as gmm, from the mix design. This is important because gmm represents the effective specific gravity of the asphalt mixture when it is fully compacted and without any air voids, thus providing a more accurate assessment of the materials involved in the mix.

The formula integrates the thickness of the asphalt layer being applied and multiplies it by the gmm to derive the target spread rate, which is essential for specifying how much asphalt binder needs to be applied to achieve the desired density and performance characteristics. The multiplier of 43.3 converts the volume to a weight measurement, aligning with typical units used in asphalt paving operations.

The other options utilize gsb (bulk specific gravity) or apply different multipliers which do not correctly correlate to the determination of spread rates for asphalt mixtures in the context given. The focus should always be on gmm when calculating target spread rates for accurate guidelines in asphalt paving applications.