The squat cylinder of compacted mix that comes out of a gyratory mold, 150 mm across and about 115 mm tall for volumetrics, or shorter for some performance tests. Techs extrude, cool, weigh and dunk them to get bulk specific gravity, and a set of two or three pucks per sample is the basis for air voids and VMA. Some labs call them pills.
Spin two pucks to Ndes and pull a Rice, I need voids on the morning sample before the plant calls.
Pucks have to cool to room temperature before the bulk gravity weighings, or the numbers wander and the voids come out wrong.
Also heard as
- pill
- specimen
- gyratory specimen
Related terms
Gyratory compactor
The lab machine that compacts mix specimens by pressing and tilting them in a rotating mold.
Rice
Lab slang for the maximum specific gravity test on loose mix, and for the Gmm value it produces.
Air voids
The small pockets of air between binder-coated aggregate in compacted mix, given as a percent of total volume.
Ndes
N design: the number of gyrations a mix specimen gets in the gyratory compactor, set by expected traffic.