Fritz-Pak Corporation · Savings & Applications Guide
The time it takes for concrete to set depends
on temperature. At low temperatures, it may
take as long as 10 hours for concrete to set,
while in warm temperatures, it may take as
few as two hours. Some fi nishing can only be
done near or after the time concrete begins to
set. It is very inconvenient for contractors to
wait long periods of time for fi nishing. Heat-
ing of aggregates and water to accelerate set
times is much more expensive than adding an
accelerator to the concrete.
One of the oldest admixtures used in the con-
crete industry is calcium chloride for set ac-
celeration, in use for about a hundred years.
It is effective in speeding up set, widely avail-
able and relatively inexpensive. However, it
has some major drawbacks: most important,
the chloride ion promotes the corrosion of re-
inforcing steel in concrete, causing failure of
structures over time.
Today, in practically all concrete construc-
tion using reinforcing steel, the use of cal-
cium chloride is forbidden. Other issues are
an increase in effl orescence, darkening of the
concrete in general, reaction with iron oxide
pigments in decorative concrete, and lower ul-
timate compressive strengths.
Fritz-Pak manufactures a powdered acceler-
ator which has none of the above problems,
because it contains no chlorides. Fritz-Pak
NCA is based on the chemical Calcium For-
mate, a non-hazardous material. Most liquid
non-chloride accelerators currently available
are based on Calcium Nitrate or Calcium Ni-
trite, which are hazardous materials requiring
special handling, storage, disposal and report-
ing to the EPA for their use.
Fritz-Pak NCA can be used to accelerate set
times by as much as 5 hours, depending on
temperature and dosage. It also reduces the
time needed to protect freshly placed con-
crete from freezing from 3 days to 2 days.
· Set Accelerating Admixture.
· Contains no damaging chlorides.
· Non-hazardous material.
· Meets the following standards: ASTM C-494
Types C and E, AASHTO M-194.