Analysis of Test Results
for Coarse Aggregates
Figure 3-1 compares the specific gravity and water absorption
results measured by the three test methods for coarse
aggregate—AASHTO T 85, Rapid AASHTO T 85 with the
CoreLok vacuum saturation, and Phunque Flask. The results
measured by the three test methods appeared more comparable
for two aggregates with lower water absorption capacities—
Columbus granite (AASHTO T 85 water absorption = 0.43 percent)
and Elmore gravel (AASHTO T 85 water absorption =
1.13 percent). For Florida limestone (AASHTO T 85 water
absorption = 5.53 percent), the Rapid AASHTO T 85 method
yielded results that were significantly different from the other
two methods, especially the absorption capacity shown in
Figure 3-1(d).
Figure 3-2 compares the standard deviations of specific gravity
and water absorption results for the three test methods for
coarse aggregate. The single-operator precision (i.e., 1S) limits
Evaluation of Candidate Test Methods
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