Theory:

Cement is obtained by granding the various row material. The degree to which the cement is drawn to smaller and smaller particals is called fineness of cement. Finer the cement higher the rate of radiation and do faster the development of strain. This is because finer cement offers greater surface area of particals for hydration I.S. 269-1976 the reduce by weight of 90 micron I.S. sieve by drying cement should not exceed 10% by the weight in case of ordinary Portland cement (O.P.C.).

Application:

The cement develop strain earlier and do form work can be removed earlier does reducing cost of construction.

Items Required:

1.       90 Micron I.S. sieve
2.       Weight balance with weight box
3.       Bristule brush 25 mm size
4.       Cement sample about 100 grams

      Diagram:





Procedure:

1.     100 gm of cement sample was taken and denoted by w1.
2.     The sample was placed on I.S. sieve no. 9
3.     Airset lump in the sample was taken fingers.
4.     Sieve was held on the both the hand and sieve with a gentally rise with out spilling the cement and keeping cement will spread on the screen carried out circular motion of sieve of the period of 15 min.
5.     The reduce left on the sieve was collected and weight. The weight of reduce is denoted as w2.

Observation 1:

Weight of the cement sample w1 = 100 gm

OBS NO.
Weight of cement (w1)
Weight of reduce (w2)
% of reduce
Mean value
1
100 gm
9 gm
9 %
-
2
100 gm
6.5 gm
6.5 %
8.16
3
100 gm
9 gm
9 %
-

Calculation 1:

1.     % of Reduce = w2/w1 X 100
                            9/100 X 100
                        =  9 %

2.     % of Reduce = w2/w1 X 100
                          6.9/100 X 100
                        = 6.5 %

3.     % of Reduce = w2/w1 X 100
                            9/100 X 100
                              =  9 %

Mean value =   9+6.5+9/3  = 8.16 %


Observation:

1.       Weight of the cement sample w1 = 100 gm
2.       Weight of reduce cement sample w2 =  9 gm

Sample Calculation:

Percentage of reduce sample =  w2/w1 X 100
                                               =  9/100 x 100
                                               =  9 %

Conclusion:

The given sample of cement contains less than / more than 10 % by weight of material course than 90 Micron sieve. Therefor it satisfied / does not satisfied the criteria as satisfied by I.S.I.

Result:

The percentage of reduce of cement sample by dry sieving  8.16 % . It is less than 10 % by weight.