Table 17. Mixture proportions per cubic meter, Michigan.
Coarse
Portland
Admixture dosage
aggregate
cement
(wgt active ingredient
(19-mm)
Sand
Type IA
w/c
per cement wgt)
Mixture
(kg)
(kg)
(kg)
ratio
(%)
Control
1045
772
391
0.41
0
PolarSet
1045
772
391
0.43
5.2
DP
1045
772
391
0.41
5.2
Table 19. Properties of fresh concrete, Michigan.
Table 18. Concrete placement
time, Michigan.
Air
Unit
Concrete
Slump
content
weight
temperature
(C)
(kg/m3)
Mixture
(cm)
(%)
Mixture
Date
Start
Control
5
3.2
2309
12
Control
15 Mar
11:00 am
PolarSet
11
5.3
2293
8
PolarSet
17 Mar
10:50 am
DP
13
8
2164
7
DP
17 Mar
1:10 pm
for warm environments. Antifreeze admixtures
Table 20. Winter cost estimate.
open new possibilities and the challenge to adapt
Shelter
standards accordingly.
Erect shelter
Antifreeze admixtures offer potential use in
(6 men, 1/2 day @ /hr)
2.00
various applications. In building construction,
Heat shelter: 1 day prior to pour and 7 days after
floor slabs and wall sections can be placed with-
(8 days @ 81 L propane/day @
||content||
.206/L3.54
out the need for temporary shelter. However,
Dismantle shelter
6.00
Materials: Assume 9 reuses (Total cost
whether or not the method of antifreeze admix-
estimated at 62)
118.00
tures may be advantageous over conventional
thermal protection depends on the specific job
Total estimated cost of shelter
79.54
circumstances. For some jobs, building a construc-
Antifreeze admixture
tion shelter may be useful for worker comfort, at
5.12 m3
Volume of concrete placed inside shelter
least during work periods.
98 cm3
Dosage of admixture per kg of cement
Because of the ability to place concrete in the
Amount of cement per m3 of concrete
391 kg
Amount of admixture per 5.12 m3 of concrete
196 L
cold and let the concrete be cold while developing
Cost of admixture to equal cost of shelter
.51/L
acceptable strengths, antifreeze mortar and con-
crete can be safely placed on cold substrates. This
option allows for applications such as joints in
precast concrete structures, repair of dams, tun-
70. Heating accounted for nearly 15 percent of
nels, foundations, etc., where a massive structure
this expense. Because antifreeze admixtures are
is cold.
still prototypes, their market price has not been
Winter paving operations can benefit greatly.
determined. However, based on the estimate de-
With antifreeze admixtures, the concrete does not
veloped for the shelter in this project (Table 20),
need to be thermally protected, and it can be placed
the break-even cost of the antifreeze admixtures
directly on cold granular bases. From the stand-
would be .51 per liter.
point of worker comfort, the highly mechanized
operation of paving makes this type of work pos-
sible at even lower temperatures than for vertical
POTENTIAL APPLICATIONS OF
building construction. Thus, there is ongoing need
ANTIFREEZE ADMIXTURES
to search for admixtures that work at very low
temperatures.
The current standards were written under the
In general, summer construction is less expen-
assumption that concrete cannot develop strength
at acceptable rates when the temperature is lower
sive, but there are applications where the job must
than 5C. Current testing methods are designed
be done in the winter and against cold substrates.
18
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