This work consists of the full-depth
removal of existing rigid pavement in areas exhibiting deterioration,
correcting the subgrade, placing and compacting asphalt concrete, and restoring
the shoulders.
The Engineer marks the limits
of the areas to be repaired. The minimum
longitudinal length of a repair is 6 feet (1.8 meters). All pavement repairs are the full lane width,
unless otherwise detailed by the plan.
The existing pavement is
sawed full-depth, at the limits established by the Engineer, with a diamond saw
blade. All diamond saw cuts shall be
perpendicular to the surface of the pavement.
Normally, the existing concrete pavement thickness is given in the
plan. There may be older projects where
the existing pavement was built thicker than specified in the new repair
plan. Concrete sawing and removal depths
may be as much as 1 inch (25 mm) greater than indicated on the repair plan
without additional compensation to the Contractor.
If there is an existing
asphalt overlay on the concrete pavement, the Contractor may elect to saw
full-depth through the asphalt concrete and the Portland cement concrete. Depending on the thickness of each material,
the Contractor may not be capable of sawing through both courses and may elect
to make an offset saw cut through the asphalt course. The Contractor would then
remove enough asphalt to allow room for a diamond saw that would saw full-depth
through the concrete pavement. If the
Contractor elects to make offset cuts to facilitate the removal, the offset cut
will not be measured for payment; only full-depth saw cuts that are made at the
limits of the removal are measured for payment.
Intermediate saw cuts made by the Contractor to facilitate removal by
the lift-out method are not measured for payment.
During hot weather, it may be
necessary for the Contractor to saw only at night or in the morning when cooler
temperatures prevail. Concrete pavement
heats up and expands as temperatures rise during hot summer days. Diamond saw blades could be pinched and
locked up while sawing the expanding pavement slabs. Some contractors use a carbide-tipped saw to
cut through pavement within the repair area.
This is permitted provided that the Contractor does not damage the base
under the pavement that is to be removed.
All perimeter saw cuts must be made with diamond saws.
Removal of the concrete
follows the full-depth sawing operation.
The lift-out method is required in order to not disturb the base under
the pavement and to minimize the damage to the adjacent pavement that is to
remain. Holes are drilled within the
removal area and lift pins are inserted.
The slab, or portion of the slab, is then removed by lifting the slab
vertically with a crane or large backhoe.
After lifting, loose debris left behind is removed by hand methods.
Removed pavement shall be
disposed of in accordance with 202.02. The Inspector shall determine and document
where and how pavement is to be disposed of by the Contractor.
The use of a pavement breaker
and backhoe for removal is not permitted unless the Engineer determines that
the lift-out method is not practical due to extensively deteriorated pavement,
the existence of asphalt concrete full-depth repairs, or old concrete pavement
repairs, which are extensively cracked and deteriorated. There will be no additional compensation for
the removal of existing pavement with a pavement breaker and backhoe.
Prior to placing asphalt
concrete in the removal area, any base or subgrade that is disturbed below the
level of clean out is removed. The
repair area must be compacted to the satisfaction of the Engineer. All vertical faces shall be cleaned and
coated with asphalt material according to 401.14.
The pavement replacement is
constructed by placing and compacting Item 301
or 448
Type 2 material in two or more lifts according to 401.16. Note: The plans for the project may specify
the use of another material. The first
lift, and all intermediate lifts, must be thoroughly and uniformly compacted
using suitable, mechanical, compaction equipment operated over the entire
replacement area.
The final lift must be
compacted using a pneumatic tire roller that conforms to 401.13. At least 18 passes should be made over all
points on the entire surface of the repair area. A pass is defined as one movement of the
roller over the surface of the patch. As
the rolling progresses, additional patching material may need to be added in
order to produce a smooth surface, flush with the existing pavement surface.
Each lift shall be
continuously compacted while the material is in a workable condition throughout
the depth of the lift.
If an overlay is not
scheduled to be placed within 60 days of the repair, the perimeter of the
repair shall be trimmed vertically 1-1/2 inches deep from the surface before
placing the final lift of asphalt concrete.
If the Contract does not include resurfacing,
the perimeter surface of the repaired areas must be sealed with a 4-inch (100
mm) wide band by applying approved 702.04
asphalt material, RS-1, RS-2, CRS-1, CRS-2, or 702.01 approved PG binder.
After completing repairs, the
existing shoulders must be repaired to the condition that existed prior to the
repair work.
1. Locate, mark, and record all areas to be repaired.
2. Measure and record saw cuts. Full-depth saw cuts are an additional pay
item paid by the linear foot.
3. Document removal of deteriorated pavement. Note condition of existing adjacent pavement.
4. Document the disposal of removed pavement.
5. Document preparation of subgrade.
6. Document that the area was cleaned and tacked with 407
tack coat.
7. Document the placement and compaction (number of lifts
and compaction method) of approved 301
or 448
Type 2 asphalt or other as specified by plan.
8. Document the location of repairs and saw cuts, measurements,
and calculations, and pay per 252.06.
9. Show documentation on CA-D-6
or other approved form.