item 320 RUBBLIZE AND ROLL
320.01
Description
320.02
Materials
320.03
Equipment
320.04
Construction Details
320.05 Method
of Measurement
320.06 Basis of
Payment
320.01 Description. This work
consists of rubblizing and rolling existing reinforced concrete pavement before
placing an asphalt concrete pavement.
320.02 Materials. Furnish filler aggregate
conforming to Item 304.
320.03 Equipment. Use a self-contained and
self-propelled unit of either the resonant frequency type or the multiple head
breaker type for rubblizing the concrete pavement.
If
using a resonant frequency unit, ensure that it is
capable of producing low amplitude, 2000-pound-force (8900 N) blows at a rate
of not less than 44 blows per second.
If
using a multiple head breaker unit, ensure that it has the capability of
rubblizing the full 12-foot (3.6 m) lane width in a single pass. Ensure
the breaking head consists of 12 to 16 hammers, each weighing 1000 to 1500
pounds (450 to 680 kg). Attach each hammer to a hydraulic lift cylinder
that operates as an independent unit, develops 2000 to 12,000 foot-pounds (2700
to 16,000 J) of energy depending on lift height selected, cycles at a rate of
30 to 35 impacts per minute, and has a maximum lift height of 60 inches (1.5
m).
Use
a vibratory steel wheel roller having a total weight of not less than 10 tons
(9 metric tons).
320.04 Construction Details. Make a
full depth saw cut or cut load transfer devices at existing joints on ramps or
mainline where the rubblizing abuts concrete pavement or approach slabs that
are to remain in place permanently or temporarily for maintenance of traffic.
Before
the rubblizing operations begin, the Engineer will designate a test
section. Rubblize the test section according to this
specification. After rubblizing, excavate a test pit, where the
Engineer designates, to check for proper particle size throughout the thickness
of the concrete. Fill in the test pit using the excavated material and
additional filler aggregate as necessary. Compact the test pit as part of
the rolling operation. Excavate at least one test pit, at the location
designated by the Engineer, for each production day or every 7040 square yards
(5886 m2), whichever is greater.
Adjust
the rubblizing procedure to maintain the proper particle sizes. Control
the operating speed of the rubblizing equipment such that: 75% of the rubblized
particles above the reinforcing steel are reduced to 3 inches (75 mm) in their
largest dimension, 90% of the rubblized particles below the reinforcing steel
do not exceed 9 inches (230 mm) in their largest dimension, and no particles
exceed 12 inches (300 mm) in their largest dimension.
Before
placing the initial asphalt concrete course, compact the rubblized pavement
with two passes of the vibratory roller. Operate the roller in the
vibratory mode and at a speed not to exceed 6 feet (1.8 m) per second.
Leave
steel reinforcement in place in the rubblized pavement. However, cut off
any exposed steel reinforcement below the surface and remove it from the site.
Fill
depressions 1 inch (25 mm) or greater in depth compared to the immediate
surrounding area resulting from the rubblizing, the compactive effort, or the
steel reinforcement removal, with the filler aggregate. Strike off excess
aggregate level with the surrounding area. Compact filled depressions
with the same roller and compactive effort previously described.
Do
not allow traffic on the rubblized pavement before the initial asphalt concrete
base and intermediate courses are in place.
Do
not allow more than 48 hours to elapse between rubblizing the pavement and
placing the initial asphalt concrete course. However, in the event of
rain, the Engineer may waive this time limitation to allow sufficient time for
the rubblized pavement to dry to the Engineer’s satisfaction. If the
Engineer waives the time limitation, cease rubblizing the pavement until the
Engineer allows paving to resume.
320.05 Method of Measurement. The
Department will measure Rubblize and Roll by the number of square yards (square
meters). The Engineer will use the actual width of the existing concrete
pavement and will measure the length along the centerline of each roadway or
ramp.
The
Department will measure the Filler Aggregate by the number of cubic yards
(cubic meters) furnished, placed, and compacted.
320.06 Basis of Payment. The
Department will pay for accepted quantities at the contract prices as follows:
Item
Unit
Description
320
Square
Yard
Rubblize and Roll
(Square Meter)
320
Cubic
Yard
Filler Aggregate
(Cubic Meter)