penetration of the crack. An adequate surface seal shall be applied to the
crack or joint to prevent the escape of epoxy. Entry points shall be
established along the crack. The crack shall be filled with a 100 percent
solid epoxy adhesive. The adhesive shall be injected into the crack at the
first entry point with sufficient pressure to advance the epoxy to the next
adjacent port. The original port shall be sealed and injection moved to
the port at which the epoxy appears. The process shall continue until each
joint and crack has been injected for its entire length. Epoxy shall be
allowed to cure in accordance with manufacturer's instructions. Sealing
materials shall then be removed and surface finished to match adjacent
existing surface.
3.5.5
Application of Concrete and Patching Mortar
Concrete and mortar shall be placed to rebuild spalled or damaged areas to
match the original surface finish, level, texture, and color. Concrete
shall be cured as specified herein. The finished appearance of the patch
shall match the adjacent existing surface.
3.6
CURING AND PROTECTION
Concrete and mortar patching shall be cured by an approved method for at
least 7 days. Immediately after placement, concrete shall be protected
from premature drying, extremes in temperatures, rapid temperature change,
mechanical injury and injury from rain and flowing water. Air and forms in
contact with concrete and mortar shall be maintained at a temperature above
10 degrees C 50 degrees F for the first 3 days and at a temperature above 0
degrees C 32 degrees F for the remainder of the specified curing period.
Materials and equipment needed for adequate curing and protection shall be
available and at the placement site prior to placing concrete and mortar.
No fire or excessive heat shall be permitted near or in direct contact with
the concrete and mortar at any time. Curing shall be accomplished by any
of the following methods, or combination thereof, as approved:
3.6.1
Moist Curing
Concrete and mortar to be moist-cured shall be maintained continuously wet
for the entire curing period. If water or curing materials stain or
discolor concrete and mortar surfaces which are to be permanently exposed,
the concrete and mortar surfaces shall be cleaned. When wooden forms are
left in place during curing, they shall be kept wet at all times. If the
forms are removed before the end of the curing period, curing shall be
carried out as on unformed surfaces, using suitable materials. Horizontal
surfaces shall be cured by ponding, by covering with a 50 mm 2 inchminimum
thickness of continuously saturated sand, or by covering with waterproof
paper, polyethylene sheet, polyethylene coated burlap, or saturated burlap.
3.6.2
Membrane Curing
Membrane curing shall not be used on surfaces that are to receive any
subsequent treatment depending on adhesion or bonding to the concrete;
except that a styrene acrylate or chlorinated rubber compound meeting COE
CRD-C 300 requirements may be used for surfaces which are to be painted or
are to receive bituminous roofing or waterproofing, or for floors that are
to receive adhesive applications of resilient flooring. The curing
compound selected shall be compatible with any subsequent paint, roofing,
waterproofing, or flooring specified. Curing compound shall be applied to
formed surfaces immediately after the forms are removed and prior to any
patching or other surface treatment except the cleaning of loose sand,
SECTION 03900
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