Conproco Corporation - CONCRETE REPAIR

Never use admixtures to accelerate or retard
setting time of polymer modified repair materials.
Never re-temper a polymer modified repair material.
Re-tempering damages the cross linking of the
polymer, which can ultimately lead to cracking
of the repair material. This type of cracking
will usually become visible between 3 - 28 days.
Adding more water than is recommended
in the instructions will weaken the material,
cause shrinkage cracking and lower strength.
Over finishing will pull water from the material
and cause surface checking or cracking.
It is always best to place and finish material
with as little troweling as possible.
Wind and high temperatures both contribute
to cracking, due to rapid evaporation of water.
Protect the repair zone with windbreaks.
Work out of direct sunlight when possible.
Cement based materials must cure properly.
Proper curing becomes more critical as the
temperatures increase. Mist cure frequently,
protect with burlene.
ACI publishes excellent manuals regarding curing.
Refer to ACI 308 Standard Practice for Curing Concrete.

Repair Mortars -
Vertical Overhead and Horizontal

When working in high temperature (80°F and above)
use cold water to retard the setting time of the repair
mortar. In extreme conditions use ice water.
Retard the setting time by keeping the bags or pails
of material out of direct sunlight and preferably in
a cool, shaded area. Keep water hoses out of
direct sunlight.
Use cool or cold water to lower the temperatures
of the substrate.
When working in lower temperatures (40 - 60°F)
use warm water to accelerate the setting time of the
repair mortar. Cool temperatures will retard curing.
Maintain 45°F for 24 hours after placement.
Mix only as much material as can be placed without
re-tempering. Different materials will cure at different
rates. Environmental conditions will affect the
open time (usable placement time) of a product.