AGGREGATES - Materials for Civil and Construction Engineers - page 175

Sieve size

100

90

80

70

60

50

40

30

20

10

0

Sieve size, mm

FIGURE 5.11 Semi-log aggregate gradation chart showing a gradation exam-

ple. See Table 5.2.

reported to the nearest whole number, except that if the percentage passing the
0.075-mm (No. 200) sieve is less than 10%, it is reported to the nearest 0.1%.
Gradation analysis results are generally plotted on a semilog chart, as shown
in Figures 5.11 and A.21.
Aggregates are usually classified by size as coarse aggregates, fine aggre-
gates, and mineral fillers (fines). ASTM defines coarse aggregate as particles
retained on the 4.75-mm (No. 4) sieve, fine aggregate as those passing the
4.75-mm sieve, and mineral filler as material mostly passing the 0.075-mm
(No. 200) sieve.

Maximum Density Gradation The density of an aggregate mix is a function of
the size distribution of the aggregates. In 1907 Fuller established the rela-
tionship for determining the distribution of aggregates that provides the
maximum density or minimum amount of voids as

b n a d i

D

P i = 100 (5.15)

where

P i = percent passing a sieve of size

size in question
size of the aggregate

d i

d i = the sieve

D = maximum