as to prevent uncontrolled cracking of the pavement. Sawing of the joints
shall commence as soon as the concrete has hardened sufficiently to permit
cutting the concrete without chipping, spalling, or tearing. The sawed
faces of joints will be inspected for undercutting or washing of the
concrete due to the early sawing, and sawing shall be delayed if
undercutting is sufficiently deep to cause structural weakness or excessive
roughness in the joint. The sawing operation shall be carried on as
required during both day and night regardless of weather conditions. The
joints shall be sawed at the required spacing consecutively in the sequence
of the concrete placement. Adequate lighting shall be provided for night
work. Illumination using vehicle headlights will not be permitted. A chalk
line or other suitable guide shall be used to mark the alinement of the
joint. Before sawing a joint, the concrete shall be examined closely for
cracks, and the joint shall not be sawed if a crack has occurred near the
planned joint location. Sawing shall be discontinued when a crack develops
ahead of the saw cut. Immediately after the joint is sawed, the saw cut
and adjacent concrete surface shall be thoroughly flushed with water and
vacuumed until all waste from sawing is removed from the joint and adjacent
concrete surface. The surface shall be resprayed with curing compound as
soon as free water disappears. Necessary precautions shall be taken to
insure that the concrete is properly protected from damage and cured at
sawed joints, but that no curing compound enters the joints. The top of
the joint opening and the joint groove at exposed edges shall be tightly
sealed with cord backer rod before the concrete in the region of the joint
is resprayed with curing compound, and shall be maintained until removed
immediately before sawing joint sealant reservoir. After expiration of the
curing period, the upper portion of the groove shall be widened by sawing
to the width and depth indicated for the joint sealer.
3.8.7
Thickened Edge Joints
Thickened edge joints shall be constructed as indicated on the drawings.
Underlying material in the transition area shall be graded as shown and
shall meet the requirements for smoothness and compaction specified for all
other areas of the underlying material.
3.9
REPAIR, REMOVAL, REPLACEMENT OF NEWLY CONSTRUCTED SLABS
3.9.1
New pavement slabs that are broken, have spalled edges, or contain cracks
shall be removed and replaced or repaired, as specified hereinafter at no
cost to the Government. Removal of partial slabs is not permitted. Not
more than 15.0 percent of each slab's edge shall be spalled. Slabs with
spalls exceeding this quantity, regardless of spall size, shall be sawn
full depth to remove the spalled face, or removed, as directed. The
Contracting Officer will determine whether cracks extend full depth of the
pavement and may require cores to be drilled on the crack to determine
depth of cracking. Such cores shall be at least 150 mm 6 inch diameter,
and shall be drilled and backfilled with a well consolidated concrete
mixture bonded to the walls of the hole with Type V, Grade 3 epoxy resin.
Drilling of cores and refilling holes shall be performed by the Contractor
at no expense to the Government.
3.9.2
Slabs with Cracks
Cracks that do not exceed 25 percent of the design thickness in depth shall
be cleaned and then pressure injected full depth with epoxy resin, Type IV,
Grade 1. Slabs containing cracks deeper than 25 percent of the design
SECTION 02753
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