seen, pushing the temperature envelope to 5C
Since this field test was conducted, the proto-
increases the length of the construction season by
type admixtures have undergone additional
nearly 80 days. More working days become avail-
research and improvement. Such research will
able at lower temperatures, to the point that con-
likely produce commercial admixtures that out-
creting is a year-round proposition without the
perform the present prototypes.
need for heat. The climate at the Soo is similar to
that of the coldest areas in the contiguous U.S.
LITERATURE CITED
ACI (1988) Cold weather concreting. ACI 306-88.
CONCLUSION
Detroit, Michigan: American Concrete Institute.
Civil Engineering (1991) Antifreeze for your con-
The admixtures performed quite well. Data
crete. December 1991, p. 10.
from nearly 2 years of laboratory testing have
shown that the prototype admixtures do not harm
Gavrish, Y. E., N.S. Khvorostovskya, and V.G.
Serbin (1974) Thermal behavior of concrete slab
the concrete and that they are capable of protect-
ing concrete down to 5C. The field tests clearly
on frozen ground bed. In Proceedings, The Second
International Symposium on Winter Concreting,
demonstrated that working with these new admix-
Moscow. Stroyizdat, vol. 1, p. 2333. (Available as
tures required no new skills. The concrete was
CRREL Draft Translation 729.)
mixed at lower temperatures; the admixture was
Korhonen, C.J. (1990) Antifreeze admixtures for
dosed into the truck, as is normally done with
cold weather concreting: A literature review. USA
some admixtures today; and the concrete was fin-
Cold Regions Research and Engineering Labora-
ished in the usual manner. The major benefit was
tory, Special Report 90-32.
that, once finished, the concrete was not damaged
Kosmatka, S. H., and W. C. Panarese (1988) Design
by exposure to freezing temperatures. The only
and Control of Concrete Mixtures, 13th edition. 5420
protection used was a plastic sheet to cover
Old Orchard Road, Skokie, Illinois: Portland
exposed areas to minimize moisture loss during
Cement Association.
curing. In addition to all of this, a tremendous
amount of thermal energy was conserved and the
U.S. Department of the Interior, Water and Power
Resources Service (1981) Concrete Manual. U.S.
resulting concrete quality was excellent.
Department of the Interior, Water and Power
The potential effect of being able to place con-
Resources Service. Washington, D.C.: Superinten-
crete at below-freezing temperatures is significant.
dent of Documents, U.S. Government Printing
Pushing the winter concreting envelope from the
current 5C limit to 5C can extend the "normal"
Office, 8th edition,
construction season by around 2 months at the Soo.
10
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