413.6 Scrub Seal Treatment
The scrub seal is a process by which an anionic charged polymer modified asphalt agent is applied to an asphalt pavement surface and scrubbed into the cracks and voids with a broom. A small layer of aggregate is then applied over the asphalt and then broomed once again, forcing the mix into the cracks and voids to form a seal. The seal is then rolled with a pneumatic tire roller. Since scrub seal is meant to be used as a preventive maintenance measure, its primary purpose is to fill cracks and seal an asphalt pavement.
This process helps to prevent light deterioration, retard progressive failures, and reduce routine maintenance service activities. The traveled way can be opened to traffic about two (2) hours after application.
Scrub sealing should be used only on pavements with AADT less than 7,500 and of sound condition. This process should be used only on stable pavements that are dry, oxidized, and cracked, since it is not intended to improve the structural condition of the pavement.