1.8.3
Air Entrainment
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NOTE: Remove last two sentences when lightweight
concrete is not required.
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Except as otherwise specified for lightweight concrete, all normal weight
concrete shall be air entrained to contain between 4 and 7 percent total
air, except that when the nominal maximum size coarse aggregate is 19 mm
3/4 inch or smaller it shall be between 4.5 and 7.5 percent. Concrete with
specified strength over 35 MPa 5000 psi may have 1.0 percent less air than
specified above. Specified air content shall be attained at point of
placement into the forms. Air content for normal weight concrete shall be
determined in accordance with ASTM C 231. Lightweight concrete in the
[_____] parts of the structure shall be air-entrained with a total air
content of 4.5 to 7.5 percent, except that if the nominal maximum size
coarse aggregate is 9.5 mm 3/8 inch or less, the air content shall be 5.5
to 8.5 percent. Air content for lightweight concrete shall be determined
in accordance with ASTM C 173/C 173M.
1.8.4
Slump
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NOTE: Use the sentence in the first set of
brackets when those admixtures are permitted by the
specifications. Add special slump requirements for
Class 8 and 9 floor slabs from ACI 302, when such
floors are to be constructed. Edit for lightweight
concrete as required.
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Slump of the concrete, as delivered to the point of placement into the
forms, shall be within the following limits. Slump shall be determined in
accordance with ASTM C 143/C 143M.
Slump
Structural Element
Minimum
Maximum
_________________________
_______
_______
Walls, columns and beams
50 mm 2 in.
100 mm 4 in.
Foundation walls, substructure
walls, footings, slabs
25 mm 1 in.
75 mm 3 in.
Any structural concrete approved
for placement by pumping:
At pump
50 mm 2 in.
150 mm 6 in.
At discharge of line
25 mm 1 in.
100 mm 4 in.
[When use of a plasticizing admixture conforming to ASTM C 1017/C 1017M or
when a Type F or G high range water reducing admixture conforming to ASTM C
494/C 494M is permitted to increase the slump of concrete, concrete shall
have a slump of 50 to 100 mm 2 to 4 inches before the admixture is added
and a maximum slump of 200 mm 8 inches at the point of delivery after the
admixture is added.] [For troweled floors, slump of structural lightweight
concrete with normal weight sand placed by pump shall not exceed 125 mm 5
SECTION 03300A
Page 18
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