equipment, mixture, or operation modified to prevent formation of such
slurry. Any slurry which does run down the vertical edges shall be
immediately removed by hand, using stiff brushes or scrapers. No slurry,
concrete or concrete mortar shall be used to build up along the edges of
the pavement to compensate for excessive edge slump, either while the
concrete is plastic or after it hardens.
3.6.3
Surface Correction and Testing
After all other finishing is completed but while the concrete is still
plastic, minor irregularities and score marks in the pavement surface shall
be eliminated by means of cutting straightedges. Such straightedges shall
be 4 m 12 feet in length and shall be operated from the sides of the
pavement and from bridges. A straightedge operated from the side of the
pavement shall be equipped with a handle 1 m 3 feet longer than one-half
the width of the pavement. The surface shall then be tested for trueness
with a straightedge held in successive positions parallel and at right
angles to the center line of the pavement, and the whole area covered as
necessary to detect variations. The straightedge shall be advanced along
the pavement in successive stages of not more than one-half the length of
the straightedge. Depressions shall be immediately filled with freshly
mixed concrete, struck off, consolidated, and refinished. Projections
above the required elevation shall also be struck off and refinished. The
straightedge testing and finishing shall continue until the entire surface
of the concrete is free from observable departure from the straightedge and
conforms to the surface requirements specified in paragraph: ACCEPTABILITY
OF WORK AND PAYMENT ADJUSTMENTS. This straightedging shall not be used as
a replacement for the straightedge testing of paragraph: Surface
Smoothness. Long-handled, flat bull floats shall be used very sparingly
and only as necessary to correct minor, scattered surface defects. If
frequent use of bull floats is necessary, the paving operation shall be
stopped and the equipment, mixture or procedures adjusted to eliminate the
surface defects. Finishing with hand floats and trowels shall be held to
the absolute minimum necessary. Extreme care shall be taken to prevent
overfinishing joints and edges. The surface finish of the pavement shall
be produced essentially by the finishing machine and not by subsequent hand
finishing operations. All hand finishing operations shall be subject to
approval and shall be modified when directed.
3.6.4
Hand Finishing
Hand finishing operations shall be used only as specified below.
3.6.4.1
Equipment
In addition to approved mechanical internal vibrators for consolidating the
concrete, a strike-off and tamping template and a longitudinal float shall
be provided for hand finishing. The template shall be at least 300 mm 1
foot longer than the width of pavement being finished, of an approved
design, and sufficiently rigid to retain its shape, and shall be
constructed of metal or other suitable material shod with metal. The
longitudinal float shall be at least 3 m 10 feet long, of approved design,
and rigid and substantially braced, and shall maintain a plane surface on
the bottom. Grate tampers (jitterbugs) shall not be used.
3.6.4.2
Finishing and Floating
As soon as placed and vibrated, the concrete shall be struck off and
screeded to the crown and cross section and to such elevation above grade
SECTION 02753
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