paver-finisher shall weigh at least 3280 kg/m 2200 lb/foot of lane width,
and shall be powered by an engine having at least 15,000 W/m 6.0
horsepower/foot of lane width. The paver-finisher shall spread,
consolidate, and shape the plastic concrete to the desired cross section in
one pass. The mechanisms for forming the pavement shall be easily
adjustable in width and thickness and for required crown. In addition to
other spreaders required by paragraph Transfer and Spreading Equipment, the
paver-finisher shall be equipped with a full width knock-down auger or
paddle mechanism, capable of operating in both directions, which will
evenly spread the fresh concrete in front of the screed or extrusion plate.
Immersion vibrators shall be gang mounted at the front of the paver on a
frame equipped with suitable controls so that all vibrators can be operated
at any desired depth within the slab or completely withdrawn from the
concrete, as required. The vibrators shall be automatically controlled so
that they will be immediately stopped as forward motion of the paver
ceases. [The paver-finisher shall be equipped with an electronic vibrator
monitoring device displaying the operating frequency of each individual
internal vibrator. The monitoring device shall have a readout display
visible to the paver operator. It shall operate continuously while paving,
and shall display all vibrator frequencies with manual or automatic
sequencing among all individual vibrators.] The spacing of the immersion
vibrators across the paving lane shall be as necessary to properly
consolidate the concrete, but the clear distance between vibrators shall
not exceed 750 mm 30 inches. The outside vibrators shall not be more than
300 mm 12 inches from the lane edge. Spud vibrators shall operate at a
frequency of not less than 135 Hz 8000 impulses/minute and an amplitude of
not less than 0.75 mm 0.03 inch and tube vibrators at a frequency of not
less than 80 Hz 5000 impulses/minute and an amplitude of not less than 0.75
mm 0.03 inch, as determined by COE CRD-C 521. The paver-finisher shall be
equipped with a transversely oscillating screed or an extrusion plate to
shape, compact, and smooth the surface and shall so finish the surface that
no significant amount of hand finishing, except use of cutting
straightedges, is required. The screed or extrusion plate shall be
constructed to provide adjustment for crown in the pavement. The entire
machine shall provide adjustment for variation in lane width or thickness
and to prevent more than 200 mm 8 inches of the screed or extrusion plate
extending over previously placed concrete on either end when paving fill-in
lanes. Machines that cause displacement of properly installed forms or
cause ruts or indentations in the prepared underlying materials and
machines that cause frequent delays due to mechanical failures shall be
replaced as directed.
1.12.5.1
Paver-Finisher with Fixed Forms
The paver-finisher shall be equipped with wheels designed to ride the
forms, keep it aligned with the forms, and spread the load so as to prevent
deformation of the forms.
1.12.5.2
Slipform Paver-Finisher
The slipform paver-finisher shall be automatically controlled and crawler
mounted with padded tracks so as to be completely stable under all
operating conditions. The paver-finisher shall finish the surface and
edges so that no edge slump beyond allowable tolerance occurs. Suitable
moving side forms shall be provided that are adjustable and will produce
smooth, even edges, perpendicular to the top surface and meeting
specification requirements for alignment and freedom from edge slump.
SECTION 02753
Page 30
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