written 5.2 years ago by |
Procedure to determine fineness of cement by dry sieving method:
Take the 100 gm of cement sample given using balance as initial weight as W1 gm.
Take 90 micron IS sieve and keep pan at bottom.
Place the measured 100 gm cement sample on 90 micron sieve and break the visible lumps present in cement using figures without pressing it on sieve.
Keep the lid on sieve.
Sieve the cement manually by giving wrist motion for 10-15 minutes, so that cement sample gets sieved completely.
Measure the weight of cement fraction retained on 90 micron sieve as W2 gm.
Calculate the % fineness of given cement as (W2 / W1 ) x 100
Repeat all above steps to get average % fineness of given cement.
IS requirement of Fineness of cement: According to IS:269, the % fineness of various cements should not exceed following limits.
i) Ordinary Portland cement (OPC): 10 % max.
ii) Rapid hardening Cement (RHC): 5 % max.
iii) Low Heat Cement (LHC): 5 % max.