NCTCOG Paving Specs •
STANDARD SPECIFICATIONS FOR PUBLIC WORKS CONSTRUCTION—NORTH CENTRAL TEXAS October 2004
303.5.5.1. Honeycombing. Special care shall be taken in placing and spading the concrete against the
forms and at all joints and assemblies so as to prevent honeycombing. Excessive voids and honeycombing in the
edge of the pavement, revealed by the removal of the side forms,may be cause for rejection of the section of slab
in which the defect occurs.
303.5.5.2. Weather Conditions. Except by specific written authorization of the OWNER, no concrete shall
be placed when the air temperature is less than 40°F (4°C) and falling but may be placed when the air
temperature is above 35°F (2°C) and rising, the temperature being taken in the shade away from artificial heat.
When and if such permission is granted,the CONTRACTOR shall furnish sufficient protective material and devices to
enclose and protect the fresh concrete in such a way as to maintain the temperature of the air surrounding the
fresh concrete at not less than 50°F (10°C)for a period of at least 5-days. It is to be distinctly understood that the
CONTRACTOR is responsible for the quality and strength of the concrete placed under any weather conditions. No
concrete shall be placed on a frozen subgrade.
303.5.5.3. Time. Concrete shall not be placed before the time of sunrise and shall not be placed later
than shall permit the finishing of the pavement during sufficient natural light.
303.5.6. Finishing.
303.5.6.1. Machine. When the concrete has been deposited, it shall be approximately leveled and then
struck off to such elevation that, when mechanically screeded and tamped, the concrete shall be thoroughly
compacted and finished to the required line, grade and section with all surface voids filled. Where bar mats or
wire mesh reinforcing is specified, method shall be in accordance with Item 303.5.3. Placing Reinforcing Steel,
Tie, and Dowel Bars.
303.5.6.1.1. Tolerance Limits. While the concrete is still workable, it shall be tested for irregularities
with a 10-ft. (3m) straightedge placed parallel to the centerline of the pavement so as to bridge depressions and
to touch all high spots. Ordinates measured from the face of the straightedge to the surface of the pavement shall
at no place exceed 1/16 inch-per-foot (1-mm-per-20-cm) from the nearest point of contact. In no case shall the
maximum ordinate to a 10-ft. (3m) straightedge be greater than 1h-in. (3mm). Any surface not within the tolerance
limits shall be reworked and refinished.
303.5.6.1.2. Edging. The edges of slabs and all joints requiring edging shall be carefully tooled with
an edger of the radius required by the plans at the time the concrete begins to take its "set" and becomes non-
workable. All such work shall be left smooth and true to lines.
303.5.6.1.3. Stamp or Die. All concrete including curbs, curb with gutter, sidewalks, alleys,
driveways and structures shall be marked by means of a substantial stamp or die so designed to make an
impression in the finish of the concrete. The stamp or die shall designate the firm name or CONTRACTOR and the
month and year in which the work was done. The design of the stamp or die shall be approved by the Engineer.
303.5.6.2. Hand. Hand finishing shall be permitted only in intersections and areas inaccessible to a
finishing machine. The addition of one-sack of cement per cubic-yard shall be required for all hand finish
concrete.
When the hand method of striking off and consolidating is permitted, the concrete, as soon as placed,
shall be approximately leveled and then struck off and screeded to such elevation above grade that, when
consolidated and finished, the surface of the pavement shall be at the grade elevation shown on the plans. The
entire surface shall then be tamped and the concrete consolidated so as to insure maximum compaction and a
minimum of voids. For the strike off and consolidation, both a strike template and tamping template shall be
provided on the work. In operation the strike template shall be moved forward with a combined longitudinal and
transverse motion and so manipulated that neither end of the template is raised from the forms during the striking-
off process. A slight excess of material shall be kept in front of the cutting edge at all times.
The straightedge and joint finishing shall be as hereinabove prescribed.
303.5.7. Curing. The curing of concrete pavement shall be thorough and continuous throughout the entire
curing period. Failure to provide proper curing as herein prescribed shall be considered as sufficient cause for
immediate suspension of the paving operations. The curing method as herein specified does not preclude the
use of any of the other commonly used methods of curing, and the OWNER may approve another method of curing
if so requested by the CONTRACTOR. If any selected method of curing does not afford the desired results, the
OWNER shall have the right to order that another method of curing be instituted. Immediately after the finishing of
the surface, the pavement shall be covered with a continuous, uniform water-impermeable coating of the type
specified in Item 303.2.13. Curing Materials. After removal of the side forms, the sides of the slab shall receive a
like coating before earth is banked against them. The solution shall be applied, under pressure with a spray
. nozzle, in such a manner as to cover the entire surfaces thoroughly and completely with a uniform film.
The rate of application shall be such as to insure complete coverage and shall not exceed 200-square-feet-
per-gallon of curing compound. When thoroughly dry, it shall provide a continuous and flexible membrane, free
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