Civil Engineering Reference
In-Depth Information
100
13
C
80
4.5C
23
C
60
4.5C
40
20
PCC with CaCl
2
Plain PCC
0
0
5
10
15
20
25
30
Curing period, days
FIGURE 6.10
Effect of CaCl
2
on strength development at different curing tem-
peratures.
The PCA recommends against using calcium chloride under the following
conditions:
1. concrete is prestressed
2. concrete contains embedded aluminum such as conduits, especially if
the aluminum is in contact with steel
3. concrete is subjected to alkali-aggregate reaction
4. concrete is in contact with water or soils containing sulfates
5. concrete is placed during hot weather
6. mass applications of concrete
The American Concrete Institute (ACI) recommends the following lim-
its to water-soluble chloride ion content based on percent weight of cement
(American Concrete Institute 1986):
Chloride Ion
Member Type
Limit, %
Prestressed concrete
0.06
Reinforced concrete subjected
to chloride in service
0.15
Reinforced concrete protected
from moisture
1.00
Other reinforced concrete
0.30
Several alternatives to the use of calcium chloride are available. These
include the following:
1. using high early strength (Type III) cement
2. increasing cement content
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