Lab Mixing Procedures/QA
Asphalt Sealer Study
LABORATORY MIXING OF CELLULOSE FIBERS (SMA/OGFC)
Mixing temperature should be approximately 300° F, based on standard viscosity AC-20 asphalt. Compaction temperature should be approximately 275° F. The cellulose fiber should be added and thoroughly blended with the hot aggregate prior to the addition of the hot asphalt cement. Care should be exercised so that the mixtures containing loose fiber are not over mixed during the initial dry mixing cycle, which could result in the shredding of the fibers.
The fiber percentage in the mix is typically 0.3% (6 lbs./ton of mix).
Mixing – Loose Fiber (Interfibe Road-Cel)
The loose fiber should be added to the fine aggregate and stirred by hand. After the loose fiber has been distributed, then this combination of fine aggregate and loose fiber may be added to the coarse fraction. After the mixture is heated to the required mixing temperature, the hot asphalt cement is added and mechanical mixing begins. This wet mixing time should require no more than 3 to 4 minutes if a mechanical mixer is used.