percent at 16 days after casting.
b. Utilize the Contractor's proposed low alkali portland cement and
ground granulated blast furnace (GGBF) slag in combination with the
proposed aggregate percentage for the test proportioning. GGBF slag
shall be used in the range of 40 percent to 50 percent of the total
cementitious material by mass. The quantity shall be determined that
will meet all the requirements of these specifications and that which
will lower the expansion equal to or less than 0.08 percent at 16 days.
**************************************************************************
NOTE: The use of Lithium Nitrate for mitigation of
alkali-silica reaction is an alternative for Navy
projects only. However, do not include in a project
specification without Navy EFD or NFESC concurrence.
**************************************************************************
c. Utilize the Contractor's proposed low alkali portland cement and a
lithium nitrate admixture. The lithium nitrate admixture may be used
in combination with either Class "F" fly ash, Class N pozzolan, or
ground granulated blast furnace (GGBF) slag, at a dosage rate as
recommended by the manufacturer.
If any of the above options does not lower the expansion to less than 0.08
percent at 16 days after casting, the aggregate(s) shall be rejected and
the contractor shall submit new aggregate sources for retesting. The
results of testing shall be submitted to the Contracting Officer for
evaluation and acceptance.
2.2.1.3
Combined Aggregate Gradation
**************************************************************************
NOTE: For Air Force Projects include the following
**************************************************************************
In addition to the grading requirements specified for coarse aggregate and
for fine aggregate, the combined aggregate grading shall meet the following
requirement.
a. The materials selected and the proportions used shall be such that
when the Coarseness Factor (CF) and the Workability Factor (WF) are
plotted on a diagram as described in d. below, the point thus
determined shall fall within the parallelogram described therein.
b. The Coarseness Factor (CF) shall be determined from the following
equation:
CF = (cumulative percent retained on the 9.5 mm
sieve)(100)/(cumulative percent retained on the 2.36 mm sieve) CF
= (cumulative percent retained on the 3/8 in.
sieve)(100)/(cumulative percent retained on the No. 8 sieve)
c. The Workability Factor WF is defined as the cumulative percent
passing the 2.36 mm No. 8 sieve. However, WF shall be adjusted,
upwards only, by 2.5 percentage points for each 42 kg 94 pounds of
cementitious material per cubic meter yard greater than 335 kg per
cubic meter 564 pounds per cubic yard.
SECTION 02753
Page 36
Previous Page
