This work consists of breaking
up an existing, non-reinforced concrete pavement using a cracking and seating
method to provide a stable base for the placement of new asphalt concrete
pavement.
The Contractor must use
equipment that is capable of producing the desired crack pattern without
extensive spalling or excessive shattering.
Extensive spalling is considered at depths greater than 1-1/4 inches.
Whip hammers cannot be used.
The Contractor must use a
50-ton pneumatic tire roller that conforms to the requirements of 204.06
(Proof Rolling) to seat the cracked concrete slabs. Pneumatic tire towing
equipment is required to move the roller forward and backward along
predetermined lines. The Contractor
shall provide information to verify the roller meets the specification
requirements.
The Contractor should provide
positive provisions, in addition to 107.07,
to contain any flying debris during cracking operation.
The Contractor must
demonstrate to the Engineer the ability of the selected equipment and procedure
to produce the desired crack pattern by cracking at least three, but no more
than 5 existing concrete slabs. The
Contractor shall furnish and apply water to dampen the cracked concrete to
enhance visual determination of the crack pattern during the test section
process. The Contractor must make
adjustments to the energy or striking pattern to maintain the desired crack
pattern.
The Contractor must provide a
crack pattern of 4-foot by 4-foot (1.2 m X 1.02 m) segments.
There may be instances where
the existing slab is already cracked into segments by age and traffic. In these cases, the Contractor must further
crack the slabs to obtain a maximum 5-foot and minimum 3-foot dimensions, both
transversely and longitudinally.
The breaking equipment shall
not be allowed to affect slabs within 1 foot of another break line, a joint, or
the edge of the concrete slab.
At least once a day, the
Contractor must apply water to a check section to allow verification of a
satisfactory crack pattern. When the
crack pattern differs from required, the Contractor must make adjustments to
the operation in order to bring the crack pattern into compliance.
The Contractor must roll the
cracked pavement until the all of the concrete pieces are seated with at least
two roller coverages. The seated pieces cannot rock or move after
seating.
The Engineer will determine
the maximum number of coverages of the roller on the
test section to ensure proper seating of segments without damage to the concrete.
Before placing asphalt
concrete, the Contractor must remove all loose pieces of concrete that are not
fully seated. All voids must be repaired
by applying 407
Tack Coat, filling with asphalt concrete, and compacting as directed by the
Engineer.
Traffic is not allowed on the
cracked concrete before the initial asphalt concrete base and the intermediate
courses are in place.
1. Document that equipment being used meets the
specifications.
2. Document the location and crack pattern obtained from
the test section. Include any additional
test sections and results.
3. Document where cracking and seating is being performed
(station-to-station), segment sizes obtained, roller coverages,
addition of tack and asphalt to fill voids, and any other observations or
issues during the operation.
4. Measure the width of the actual existing pavement and
the length along the centerline of each roadway and calculate square yards for
payment.
5. Document using form CA-D-3A
or other approved forms.