line of a crowned pavement or along the highest side of a sloped
cross-section. The mixture shall be placed in consecutive adjacent strips.
On areas where irregularities or unavoidable obstacles make the use of
mechanical spreading and finishing equipment impractical, the mixture may
be spread, raked, and luted by hand tools. The longitudinal joint in the
RMP shall be offset from the longitudinal joint in the underlying asphalt
pavement by at least 300 mm 1 foot.
3.9.1
Rollers
Small (1.8 metric ton 2-ton maximum) tandem steel wheel vibratory rollers
shall be used to smooth over the surface of freshly placed open graded
bituminous mixture. The vibratory unit shall be turned off during
smoothing of the bituminous mixture. Rollers shall be in good condition,
capable of operating at slow speeds to avoid displacement of the bituminous
mixture. The number, type, and weight of rollers shall be sufficient to
roll the mixture to the voids total mix requirement of 25 to 35 percent
while it is still in a workable condition. The use of equipment which
causes excessive crushing of the aggregate will not be permitted.
3.9.2
Smoothing of Open Graded Bituminous Mixture
The open graded bituminous mixture shall be smoothed with one to three
passes of the prescribed roller without vibration. The temperature of the
freshly placed open graded bituminous mixture shall be low enough to
prevent excessive shoving or cutting of the mat under the roller.
3.9.3
Protection of Ungrouted Pavement
The Contractor shall protect the ungrouted pavement and its appurtenances
from traffic and against contamination from mud, dirt, wind blown debris,
waterborne material, or any other contamination which could enter the void
spaces of the open graded bituminous mixture before grout application.
Protection against contamination shall be accomplished by keeping the
construction site clean and free of such contaminants and by covering the
ungrouted pavement with protective materials when directed by the
Contracting Officer. Such protective materials shall consist of rolled
polyethylene sheeting as described in paragraph WEATHER LIMITATIONS. The
sheeting may be mounted on either the paver or a separate movable bridge
from which it can be unrolled without dragging over the pavement surface.
3.10
PREPARATION OF SLURRY GROUT
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NOTE: Generally, the cross polymer resin should be
added to the grout mixture at the batch plant if the
haul distance is less than 20 minutes. If the haul
distance is greater than 20 minutes, the cross
polymer resin should be added to the grout mixture
at the job site.
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The slurry grout shall be mixed using a batch plant, portable mixer and/or
ready-mix truck and according to mix proportions stated in the approved
JMF. The cross polymer resin shall be added to the mixture after all other
ingredients have been thoroughly mixed. When using ready-mix trucks for
transporting slurry grout, the grout mixture shall be thoroughly mixed at
the job site immediately before application for a minimum of 10 minutes.
Thorough mixing shall be accomplished by rotating the mixing drum at the
SECTION 02746
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