approved material, prior to overlying materials being placed. Any
method which does not hold the form securely or which damages the
existing pavement shall be immediately discontinued. Prior to
setting forms for paving operations, the Contractor shall
demonstrate his proposed form setting procedures at an approved
location and shall not proceed further until the proposed method
is approved by the Contracting Officer.
3.5.5.2
Form Removal
Forms shall remain in place at least 12 hours after the concrete has been
placed. When conditions are such that the early strength gain of the
concrete is delayed, the forms shall be left in place for a longer time, as
directed. Forms shall be removed by procedures that do not injure the
concrete. Bars or heavy metal tools shall not be used directly against the
concrete in removing the forms. Any concrete found to be defective after
form removal shall be repaired promptly, using procedures specified
hereinafter or as directed.
3.5.6
Slipform Paving
**************************************************************************
NOTE: Retain slipform paving as an option unless
there are specific, valid reasons for deleting it.
Be sure all other paragraphs correlate with choice
made here.
**************************************************************************
3.5.6.1
General
conform to the requirement of paragraph EQUIPMENT, all requirements
specified above in subparagraphs, General, Consolidation, Operation, and
Required Results, and as specified herein. The slipform paver shall shape
the concrete to the specified and indicated cross section, meeting all
tolerances, in one pass. The slipform paver shall finish the surface and
edges so that only a very minimum isolated amount of hand finishing is
required. If the paving operation does not meet the above requirements and
the specified tolerances, the operation shall be immediately stopped, and
the Contractor shall regroup and replace or modify any equipment as
necessary, modify paving procedures or modify the concrete mix, in order to
resolve the problem. The slipform paver shall be automatically
electronically controlled from a taut wire guideline for horizontal
alignment and on both sides from a taut wire guideline for vertical
alignment, except that electronic control from a ski operating on a
previously constructed adjoining lane shall be used where applicable for
either or both sides. Automatic, electronic controls for vertical
alignment shall always be used on both sides of the lane. Control from a
slope-adjustment control or control operating from the underlying material
shall never be used. Side forms on slipform pavers shall be properly
adjusted so that the finished edge of the paving lane meets all specified
tolerances. Dowels in longitudinal construction joints shall be installed
as specified below. The installation of these dowels by dowel inserters
attached to the paver or by any other means of inserting the dowels into
the plastic concrete shall not be permitted. [If a keyway is required, a
0.45 to 0.55 mm 26 gauge thick metal keyway liner shall be installed as the
keyway is extruded. Keyway forms shall not vary more than plus or minus 3
mm 1/8 inch from the dimensions indicated and shall not deviate more than
plus or minus 6 mm 1/4 inch from the mid-depth of the pavement. There
SECTION 02753
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