item 321 CRACKING AND SEATING EXISTING Non-
reinforced CONCRETE PAVEMENT
321.01
Description
321.02
Equipment
321.03
Construction Details
321.04 Method
of Measurement
321.05 Basis of
Payment
321.01 Description. This work consists of
cracking and seating existing non-reinforced concrete pavement or concrete base
before placing an asphalt concrete pavement.
321.02 Equipment. Use devices for cracking the
concrete capable of producing the desired crack pattern without extensive spalling or excessive shattering. Extensive spalling is spalling over 1 1/4
inches (30 mm) in depth. Do not use whiphammers.
Use
watering equipment capable of wetting the cracked surface uniformly to reveal
the crack pattern.
Use
a 50-ton (45 metric tons) pneumatic tire roller conforming to the requirements
of Item 204 for seating the cracked concrete
slabs. Use pneumatic tire towing equipment capable of moving the roller
forward and backward along predetermined lines.
321.03 Construction Details.
Demonstrate, to the Engineer’s satisfaction, the ability of the selected
equipment and procedures to produce cracking of acceptable quality by cracking
at least three, but no more than five, existing concrete slabs. When
cracking the test sections, furnish and apply water to dampen the cracked
concrete to enhance visual determination of the cracking pattern. In
addition to 107.07, provide positive
provision to contain any flying debris during cracking operations.
Crack
existing concrete into nominal 4 x 4-foot (1.2 x 1.2 m) segments. In the
event existing panels are already cracked into segments, crack these segments
further into nominally equal-sized square or rectangular pieces having
longitudinal and transverse dimensions not more than 5 feet (1.5 m) and not less
than 3 feet (0.9 m), wherever feasible. Do not allow the cracking
equipment to impact the slabs within 1 foot (0.3 m) of another break line,
joint, or the edge of the concrete.
Furnish
and apply water to a check section at least once each day to verify that a
satisfactory crack pattern is being maintained. Make adjustments to the
energy or striking pattern when the Engineer deems it necessary, based on the
check sections.
Roll
the cracked concrete until the concrete pieces are firmly seated. Perform
rolling with at least two coverages as specified in
Item 204. The Engineer will determine the
maximum number of coverages of the roller on the test
sections to ensure seating without damage to the concrete.
Before
placing the asphalt concrete, remove all loose pieces of broken concrete that
are not firmly seated. Repair all voids, such as spalls, removed loose
pieces, joints, or cracks that, in the Engineer’s opinion, will make uniform
compaction of the first asphalt concrete course difficult. Repair voids
by applying 407 tack coat, filling with asphalt
concrete, and compacting as directed by the Engineer.
Do
not allow traffic on the cracked concrete before the initial asphalt concrete
base and intermediate courses are in place.
321.04 Method of Measurement. The
Engineer will measure the area of existing non-reinforced concrete pavement or
concrete base satisfactorily cracked and seated in square yards (square
meters). The Engineer will measure the actual width of the existing concrete,
and will measure the length along the centerline of each roadway or ramp.
321.05 Basis of Payment. Payment
is full compensation for furnishing all labor, equipment, materials, and
incidentals necessary to complete this work; for all crack pattern test and
check sections including water; and for repairing of joint, cracks, spalls, and
voids.
The
Department will pay for the accepted quantities at the contract price as
follows.
Item
Unit
Description
321
Square
Yard
Cracking and Seating Existing Non-
(Square
Meter)
Reinforced Concrete Pavement