Figure 2-8. Bulking factor curves.
EXAMPLE PROBLEM: Using the final mix proportions, adjust the design mix to account for 6 percent FSM on
the fine aggregate (FM = 2.70) and 2 percent FSM on the coarse aggregate. Original mix design was--
Cement
= 7.05 sacks (Type IA)
Water
= 38.6 gallons
CA
= 17.0 f or 1,768 lb/cy
FA
= 10.5 cf or 1,083 lb/cy
Air content
= 5 percent
Step 1. Determine the amount of water (in gallons) on the aggregate.
CA 1,768 lb/cy x 0.02 = 35.36 lb/cy of water
FA 1,083 lb/cy x 0.06 = 64.98 lb/cy of water
Total weight of water = 100.34 lb/cy
Step 2. Reduce the original amount of mixing water by the amount contributed by the aggregates as determined
in Step 1. Therefore, 38.6 gallons - 12 gallons = 26.6 gallons of water which must be added to the mix.
EN5466
2-22
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