What is VFA in asphalt?
Similarly, you may ask, what is VMA in asphalt?
Let's look at VMA, which stands for “Voids in Mineral Aggregate.” VMA is the space between the rocks that can be filled with asphalt. The space filled with asphalt is known as VFA (Voids Filled with Asphalt). The remaining space is air voids.
Furthermore, how do you calculate air voids in asphalt? This volume is typically quantified as a percentage of air voids by volume and expressed as “percent air voids”. Percent air voids is calculated by comparing a test specimen's bulk specific gravity (Gmb) with its theoretical maximum specific gravity (Gmm) and assuming the difference is due to air.
Consequently, what is effective asphalt content?
Total asphalt content is the amount of asphalt that must be added to the mixture to produce the desired mix qualities. Effective asphalt content is the volume of asphalt not absorbed by the aggregate; the amount of asphalt that effectively forms a bonding film on the aggregate surfaces.
How do you calculate voids in mineral aggregate?
CALCULATION VMA = Voids in mineral aggregate, in percent of bulk volume, Gsb = Bulk specific gravity of the aggregate, Gmb = Bulk specific gravity of compacted mix, Ps = Aggregate, percent by total weight of mix. Where: P1 = Percent by weight of aggregate 1, etc., G1 = Bulk specific gravity of aggregate 1, etc.