Checking of materials is an essential part of civil engineering as the life of structure is dependent on the quality of material used. Following are the tests to be conducted to judge the quality of cement. 1. Fineness
4. Initial and Final Setting Time of Cement
FINENESS OF CEMENT:
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 than specified mesh size. Apparatus:
The apparatus used are
i) 75µm IS Sieve
ii) Balance capable of weighing 10g to the nearest 10mg
iii) A nylon or pure bristle brush, preferably with 25 to 40mm iv) bristle, for cleaning the sieve
Figure No. Sieve No. 200 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.
Test To Check Soundness Of Cement:
Soundness of cement is determined by Le-Chatelier method as per IS: 4031 (Part 3) – 1988. Apparatus – The apparatus for conducting the Le-Chatelier test should conform to...