2.1.4
Water
Water for mixing and curing shall be fresh, clean, potable, and free of
injurious amounts of oil, acid, salt, or alkali, except that nonpotable
water may be used if it meets the requirements of COE CRD-C 400.
2.2
CONCRETE MIXTURE PROPORTIONING
**************************************************************************
NOTE: Well-rounded natural aggregates are preferred
due to the increased flowability of concrete
containing these aggregates. If crushed aggregates
are used, the fine aggregate and cementitious
materials contents may have to be increased to
achieve satisfactory flowability. If crushed
aggregate is used, increase the specified minimum
cement content to 335 kg per cubic meter (564 pounds
per cubic yard).
**************************************************************************
Concrete Mixture Proportioning shall conform to the following:
a. Maximum Water-Cement Ratio - The maximum water-cement ratio by
weight of equivalent portland cement shall be 0.50, unless otherwise
approved in writing.
b. Cement Content - The cement content of the concrete shall be within
the range from a minimum of [279 kg] [470 pounds] [_____] to a maximum
of 446 kg per cubic meter 752 pounds per cubic yard. When a pozzolan
is used, the total absolute volume of cementitious material shall be
within the same range in absolute volume as previously specified. Of
the total absolute volume of cementitious materials, between 20 and 30
percent may be pozzolan that meets the requirements of paragraph
POZZOLAN, OTHER THAN SILICA FUME. [If GGBFS is used, it shall not
exceed 25 percent by absolute volume, and percentage shall be as
approved before mixture proportioning studies commence.]
c. Nominal Maximum-Size Coarse Aggregate - The nominal maximum-size
coarse aggregate shall be [19.0 mm 3/4 inch] [25.0 mm 1 inch].
d. Fine Aggregate - Fine aggregate shall comprise approximately 40 to
50 percent, by volume, of the total aggregate.
e. Air Content - Air Content as determined by ASTM C 231 shall be 6.0
1.5 percent.
f. Slump - Slump shall be determined by ASTM C 143/C 143M and shall be
between 150 and 225 mm 6 and 9 inches.
2.2.1
Responsibility of Mixture Proportioning
Proportioning of concrete for use in construction of the cutoff wall shall
be the responsibility of the Contractor and shall be performed by a
laboratory complying with ASTM C 1077.
2.2.2
Concrete Proportioning
**************************************************************************
NOTE: There is no requirement for fc'. The results
SECTION 03373
Page 17
Previous Page
