all RCC shall be moist cured for 14 days. Conventional concrete made with
Type I portland cement shall be moist cured for 7 days. Conventional
concrete shall be moist cured by covering with saturated nonstaining burlap
or cotton mats. New burlap or cotton mats shall be rinsed to remove
soluble substances before using. Concrete that is moist cured shall be
maintained continuously, not periodically, wet for the duration of the
entire curing period. Water for curing shall comply with the requirements
of paragraph WATER. If the water or mats cause staining or discoloration
of permanently exposed concrete surfaces, the surfaces shall be cleaned by
a method approved by the Contracting Officer. When wood or metal forms are
left in place during curing, the forms shall be kept continuously wet,
except for sealed insulation curing in cold weather. RCC may be cured with
saturated cotton or burlap mats in lieu of the approved fog spraying
equipment.
3.4.2
Cold-Weather Protection
**************************************************************************
NOTE: See the concrete materials DM or thermal
study for the optional numbers.
**************************************************************************
The air and forms in contact with the RCC and any conventional concrete
shall be maintained at a temperature above 0 degrees C 32 degrees F for
[14] [_____] days. In addition, at the time insulation or protection is
removed, the air temperature adjacent to the RCC surfaces shall be
controlled so that the concrete near the surface will not be subjected to a
temperature differential of more than 15 degrees C 25 degrees F (as
determined by observation of ambient air and concrete temperatures).
3.4.3
Special Cold-Weather Insulation Protection
**************************************************************************
NOTE: See the appropriate DM for use of this
paragraph and to fill in the blanks.
**************************************************************************
In addition to the requirements specified in paragraph COLD-WEATHER
PROTECTION, all RCC and any conventional concrete placed at the same time
and in direct contact with the RCC shall receive special insulation
protection as described for the following time periods:
a.
[_____].
b.
[_____].
The insulation shall provide an R value not less than [_____] square meter
degree Celsius per watt hour square foot degree Fahrenheit per BTU.
3.4.4
Hot-Weather Protection
When ambient air temperatures exceeds 30 degrees C 90 degrees F and as soon
as the conventional concrete and RCC is sufficiently hard to withstand
washing of surface mortar, water by fog spraying shall be applied in a
controlled manner to provide evaporative cooling. Water shall be applied
at such a rate that it quickly evaporates and such that the surface remains
continuously moist without ponding. In addition, when surface materials
begin to dry and while the RCC placement, spreading, and compaction process
is still underway and until the concrete has sufficiently hardened to
SECTION 03701
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