Test For Cement

Laboratory test:

      1. Chemical Composition test

•  Lime saturation Factor (LSF): This is the ratio of Lime% to % of Silica, Alumina and Iron oxide. This value should be in between 1.02-0.66.

                 Cao - 0.7SO3                         

  ( 2.8SiO2+1.2Al2O3+0.65Fe2O3)

• Ratio of % Alumina (Al2O3) to Iron oxide (Fe2O3) shall not be less than 0.66

• Wt. of Insoluble residue shall not be more than 4%

• Wt. of Magnesia (MgO) shall not be more than 6%

• Shall not more than 5% loss on ignition.

2. Normal Consistency Test

• 500 gm of cement @27 0C 90% Humidity   mix  with water( 23-24% wt of cement).

• Fill paste in the mould  having dimension 80 mm dia , 40 mm depth

• Normal Consistency if define as the cement paste which allow penetration of Vicat Plunger(10 mm dia & 500 mm Length) 5 to 7 mm from bottom or 33 mm to 35 mm from top.

• Change the % of water till above given criteria achieve. that % of water is called Normal Consistency of Cement. 

• Vicat Plunger : 300 gm , 50 mm length, 10 mm dia 

3. Intial Setting Time

• Initial setting time is the time after which cement start losing its plasticity.

• It should not be less than 30 min and  more than 60 min for OPC

• Take 500 gm of cement @27 0C 90% Humidity  mix with water ( 0.85 Normal consistency of  cement).

• Time at which Vicat Plunger having 1 mm square size penetrate 5 mm to 7 mm from bottom.

4. Final Setting Time

• Final setting time is the time cement paste lost complete plasticity and start hardening.

• Its should not be more than 10 Hr for OPC (ordinary Portland cement).

• Needle makes impression but collar fail to do.

• Procedure is same as above , dimension of Vicat is Annular Collar of 10 mm size.

5. Soundness Test

• Soundness is determine by "Le Chatellier's Test if Lime(CaO) is in excess amount and Autoclave Test if Lime and Magnesia(MgO) both are in excess amount.

• Le- Chatellier's is the split cylinder method value should not be more than 10 mm. Split Cylinder Depth and Height of Cylinder having arm is 30 mm both.

• Autoclave Test value should not be exceed 0.8% of length dimension or 25 mm. pressure applied 21kg/cm2 for period of 3 Hr.