Surface Preparation for Tack Coat
Posted by Jesse Willoughby on Wed, May 06, 2009 @ 05:06 AM
The Contractor must clean the old pavement if it is dirty or covered with debris. A power broom is normally used, but in extreme cases flushing with water may be necessary. The worst enemy of a tack coat is dry dust. A slightly damp (not wet) surface is preferable to a dry, dusty one. If all the dust cannot be removed, the old surface should be moistened slightly 0.05-0.10 gal/sq. yd. using a water truck with a high-pressure spray bar.
Curbs, manholes, inlets, and the like are usually dirty and require cleaning with a hand broom prior to the application of a tackcoat.