DETERMINATION OF SOUNDNESS OF CEMENT
Aim: To determine the soundness of Ordinary Portland Cement.
a) Weighing Balance
b) Le-Chataleier moulds
c) Vicat apparatus
d) Water bath
e) Miscellaneous ( trowels, tray, stop watch etc.)
- Take 400gm of Cement and find its standard consistency.
- Place the lightly oiled Le- Chatelier mould on a lightly oiled glass sheet
- Prepare a cement paste formed by gauging cement with 0.78 times the water required to give a paste of standard consistency.
- Fill the Le-Chatelier mould with this cement paste made in step (iii) of procedure.
- Cover the mould on the top with another piece of lightly oiled glass sheet.
- Place a small weight on this covering glass sheet and immediately submerge the whole assembly in water at a temperature of 27° to 32° degree Celsius and keep it there for 24 hours.
- Measure the distance between the indicator points. Submerge the mould again in water. Heat the water and bring to boiling point in about 25-30 minutes and kept it boiling for 3 hours.
- Removal the mould from water allows it to cool and measure the distance between the indicator points. The difference between these two measurements represents the expansion of cement.
This must not exceed 10mm for ordinary, rigid hardening & low heat Portland cements. If in case the expansion is more than 10mm as tested above, the cement is said to be unsound.