15 March 2001
more than one pass is applied, the previous layer should fully cure before applying the second
6.3.3. Roll the slurry. The slurry shall be rolled to reduce the voids, limit surface imperfections,
and increase the slurry's resistance to water. The rolling should be performed after the slurry has
cured enough to support the roller without removing any of the slurry mixture. A 5-ton
(4,540-kilogram) pneumatic-tire roller with tire pressures of 50 pounds per square inch
(345 kilopascals) should be used to roll the slurry.
6.3.4. Cure the slurry. The time to allow for curing will vary according to the amounts of the
emulsion and aggregate. The slurry could cure by evaporation of water from the surface, by
deposition of asphalt on the aggregate which frees the water, or by a combination of these. If
curing is from top to bottom, the material at the top will cure faster than the material at the bottom.
Before opening the treated area to traffic, the slurry seal shall be fully cured.
6.4. Problem Areas.
To ensure proper slurry machine calibration and correct mixture,
strip should be used. When hand applying the slurry, it should not be overworked; this causes
the emulsion to break prematurely. If possible, the second lane should be applied while the edge
of the previous lane is still fluid and workable. If the previous lane's edge is not workable, then
allow the slurry material to cure enough for the spreader box not to damage the previous lane.
Since material buildup on the burlap drag causes streaking and gouging, the burlap drag should
be kept clean and it should be replaced when necessary. The flexible lining of the spreader box
should be inspected for wear or accumulation of cured slurry.