Theory:
The
purpose of fineness modulus test is to know the character of the aggregate to
be used as to wheather it is fine medium or coarse. The particle size
distribution given an idea of greeding of the aggregate or not. Fineness
modulus is an impurical factor which is 100th of the sum of
cumulative percentage of the fraction of a sample retain on each successively
in the order.
GRIDING
– Griding of aggregate is the particle size distribution of the aggregate. It
is plated as curve on a semi log graph. It indicates wheather the material is
well graded or not. If it is well graded then the various sizes are present.
Application:
The
application of fineness modulus and particle size distribution of aggregate is
to fine the aggregate is coarse or fine wheather it can be used in making
mortar or concrete. If not what corrective action as to be taken is decided
upon. Then the particles distribution study given an idea as to weather the
material well grade or not. Also weather it is suitable for used in concrete.
If the grading does not satisfied the specification corrective action as to be
taken.
Items Required:
1. A set of I.S. Sieve
For
fine aggregate – 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron, 50 micron.
For
coarse aggregate – 80 mm, 60 mm, 40 mm, 20 mm, 10 mm, 4.75 mm.
2. Weighing balance accuracy
upto 0.1 gm.
3. Shovel soft brush.
4. Fine aggregate 2 kg.
5. Coarse aggregate.
Procedure:
1. Sample the required
quantity of resepective sampe was taken from stock
2. The weight of the sample to
be brought from job 8 to be taken from sieving of maximum size of
aggregate.
3. The sample was brought air
dry condition before weighing sieving by allowing it to dry and room
temperature by heating.
4. Cleaned sieves are used and
starting from largest size to successively smaller and smaller size start sieveing
operation.
5. Each sieve was shaked
seperatly over acican tray for operior of not less than 2 minutes. More the
sieves backword and for anti-clockwise with frequent jerking so as to keep the
material moving over the sieves suface avoid spelling of aggregate during above
operation. Any lumps of fine material may be broken by pressure with fingers
against the side of sieve.
6. The material retain on each
sieve.
7. To find out the fineness
modulus and fine aggregate and coarse aggregate.
Conclusion:
1. The sand for fine aggregate
is well graded or not well graded.
2. Value of fine aggregate are
satisfied or does not satisfied.
3. The sand for coarse
aggregate is well graded or not well graded.
4. Value of coarse aggregate
are satisfied or does not satisfied.
Diagram:
I.S. Sieve Set For
Fine & Coarse Aggregate
Observation Table:
Weight
of Fine Aggregate = 2 Kg
I.S. Sieve
|
Weight retain
in gm
|
Cumulative
Weight retain
|
Cumulative %
percent retain
|
% percent
passing
|
4.75
|
132
|
132
|
6.6
|
93.4
|
2.36
|
272
|
404
|
20.2
|
79.8
|
1.18
|
510
|
914
|
45.7
|
54.3
|
600
|
390
|
1304
|
65.2
|
34.8
|
300
|
420
|
1724
|
86.2
|
13.8
|
150
|
254
|
1978
|
98.9
|
1.1
|
75
|
2277
|
2000
|
100
|
0
|
-
|
2000
|
-
|
322.8
|
-
|
Cumulative
weight = 132 gm / 2000 gm X 100 = 6.6
Total
cumulative weight retained = 322.8
Weight
of Coarse Aggregate = 14 Kg
I.S. Sieve
|
Weight retain
in gm
|
Cumulative
Weight retain
|
Cumulative %
percent retain
|
% percent
passing
|
80
|
0
|
0
|
0
|
100
|
60
|
0
|
0
|
0
|
100
|
40
|
6900
|
6900
|
49.28
|
50.72
|
20
|
3140
|
10040
|
71.71
|
28.28
|
10
|
2584
|
12624
|
90.17
|
9.82
|
4.75
|
1169
|
13793
|
88.52
|
1.47
|
Less than
4.75
|
207
|
14000
|
100
|
0
|
-
|
14000
|
-
|
-
|
-
|
Total
Cumulative weight retained = 309.69
Result:
1. Fineness modules of fine
aggregate was found to be = 4.228
2. Fineness modules of coarse
aggregate was found to be = 3.0968
3. The grading of the fine and
coarse aggregate are shown in the graph ploted.
