fineness modulus

Definition

Construction

  • A factor obtained by adding the total percentages by weight of an aggregate sample retained on each of a specified series of sieves, and dividing the sum by 100. In the U.S. the standard sieve sizes are No. 100 (150 micrometer), No.50 (300 micrometer), No.30 (600 micrometer), No.16 (1.18 mm), No.8 (2.36 mm) and No.4 (4.75 mm), and 3/8" (9.5 mm), 3/4" (19 mm), 1-1/2" (38.1 mm), 3" (75 mm), and 6" (150 mm).
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