civil engineering-->>Test To Check Fineness Of Cement

Test To Check Fineness Of Cement

FINENESS
So we need to determine the fineness of cement by dry sieving as per IS: 4031 (Part 1) – 1996.The principle of this is that we determine the proportion of cement whose grain size is larger then specified mesh size.
The apparatus used are 90µm IS Sieve, Balance capable of weighing 10g to the nearest 10mg, A nylon or pure bristle brush, preferably with 25 to 40mm, bristle, for cleaning the sieve.
Sieve shown in pic below is not the actual 90µm seive.Its just for reference.

Procedure to determine fineness of cement
i) Weigh approximately 10g of cement to the nearest 0.01g and place it on the sieve.
ii) Agitate the sieve by swirling, planetary and linear movements, until no more fine material passes through it.
iii) Weigh the residue and express its mass as a percentage R1,of the quantity first placed on the sieve to the nearest 0.1 percent.
iv) Gently brush all the fine material off the base of the sieve.
v) Repeat the whole procedure using a fresh 10g sample to obtain R2. Then calculate R as the mean of R1 and R2 as a percentage, expressed to the nearest 0.1 percent. When the results differ by more than 1 percent absolute, carry out a third sieving and calculate the mean of the three values.

Reporting of Results
Report the value of R, to the nearest 0.1 percent, as the residue on the 90µm sieve.

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