Volume-IF - JantERmantER

DCPL-K4A02
3.4.2.3 Grading Requirements of Coarse Aggregates
The coarse aggregates shall conform to one of the gradings given in Table-
IV, provided, however, the use of Grading No. 1 shall be restricted to subbase
courses only.
TABLE-IV
GRADING REQUIREMENTS OF COARSE AGGREGATES
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Grading Size range Sieve Percent by weight
No. designation passing the sieve
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1. 90 mm to 40 mm 100 mm 100
80 mm 65-85
63 mm 25-60
40 mm 0-15
20 mm 0-5
2. 63 mm to 40 mm 80 mm 100
63 mm 90-100
50 mm 35-70
40 mm 0-15
20 mm 0-5
3. 50 mm to 20 mm 63 mm 100
50 mm 95-100
40 mm 35-70
20 mm 0-10
10 mm 0-5
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3.4.2.4 Screenings
Screenings to fill voids in the coarse aggregate shall generally consist of
the same material as the coarse aggregate. However, where permitted,
predominantly non-plastic material such as moorum or gravel (other than
rounded river borne material) may be used for this purpose provided liquid
limit and plasticity index of such material is below 20 and 6 respectively and
fraction passing 75 micron sieve does not exceed 10 percent.
As far as possible, screenings shall conform to the gradings set forth in
Table-V Screenings of Type A in Table shall be used with coarse
aggregates of grading 1 in Table IV. Screenings of Type A or B, shall be
used with coarse aggregates of grading 2. Type B screenings shall be used
with coarse aggregates of grading 3.
TABLE-V : GRADINGS FOR SCREENINGS
(PCA.775.S034sca7) V.II-D2/S-VII : 10