Short for Superior Performing Asphalt Pavements, the mix design and binder specification system used in place of the Marshall and Hveem methods on most North American highway work. It combines PG binder selection by climate, aggregate consensus properties such as angularity and clay content, and volumetric design in a gyratory compactor at a gyration level set by traffic. A Superpave mix is named by its nominal maximum aggregate size and design traffic, such as a 12.5 mm mix for 3 to 30 million ESALs.
It's a Superpave 12.5 at 100 gyrations, so don't expect it to roll like the county's Marshall mix.
Also heard as
- SP
- Superpave mix
Related terms
PG
Performance Grade: the binder rating that names the hottest and coldest pavement temperatures a binder can handle.
Gyratory compactor
The lab machine that compacts mix specimens by pressing and tilting them in a rotating mold.
Ndes
N design: the number of gyrations a mix specimen gets in the gyratory compactor, set by expected traffic.
NMAS
Nominal maximum aggregate size: the sieve size used to name a mix, such as a 9.5 mm or 19 mm mix.
Air voids
The small pockets of air between binder-coated aggregate in compacted mix, given as a percent of total volume.