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NOTE: Use for high durability and low permeability.
The initial cost of the concrete will increase, and
supervision at the batch plant, finishing, and
curing is necessary. A HRWR must be used with
silica fume, the slump can be increased 50 to 125 mm
(2 to 5 inches) 2 to 5 inches without reducing
strength. Finishing may be more difficult. Proper
curing is essential because there is a tendency for
plastic shrinkage cracking.
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ASTM C 1240, provide silica fume that is a by-product of silicon or
ferrosilicon production. Provide [5] [7.5] [10] percent by weight of the
total cementitious material.
]2.4.2
Water
Water shall be fresh, clean, and potable; free from injurious amounts of
oils, acids, alkalis, salts, organic materials, or other substances
deleterious to concrete.
2.4.3
Aggregates
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NOTE: Include the first bracketed item on large
concrete projects, where concrete is exposed to
seawater, alkali soils, moist conditions, or the
quality of the aggregates is questionable.
When the use of alkali-reactive aggregates is
permitted, delete everything after the first two
sentences, add the following, and add paragraph
entitled "Additional Curing When Using
Alkali-Reactive Aggregates" as follows:
"Alkali-reactive aggregates may be used where not
exposed to either seawater or alkali soil
conditions, and when used with one of the following
cements and tested in accordance with ASTM C 441 to
ensure that a 75 percent minimum reduction of
expansion due to alkali-aggregate reaction is
provided.
1. ASTM C 150 low alkali cement (Table 1A, maximum
of 0.60 percent equivalent Na2O).
2. ASTM C 59/C 59M5M ASTM C 59/C 59M5 blended
cement.
3. ASTM C 150 low alkali, Type I or II cement with
fly ash, pozzolan, or ground slag.
Furnish a mix design utilizing alkali-reactive
aggregates with a maximum water-cement ratio of
0.45."
"Additional Curing When Using Alkali-Reactive
SECTION 03300N
Page 25
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