SV Technocrats India’s Le Chatelier Mould is used to determine the soundness of cement by measuring its expansion due to uncombined lime or magnesia when subjected to boiling water. It is a standard apparatus used in IS: 4031 (Part 3), ASTM C151, and BS 4550.
Components of Le Chatelier Mould
Split Cylindrical Brass Mould –
30 mm internal diameter
30 mm height
0.5 mm thickness
Slit on one side (to allow expansion measurement)
Two Glass Plates – Used to enclose the cement paste sample.
Weight (for stability) – To keep the mould in position during testing.
Measuring Scale/Caliper – For precise expansion measurement.
Water Bath (Boiling Unit) – Maintains water at boiling temperature for the test.
Testing Procedure (IS 4031 - Part 3: Soundness of Cement)
1. Preparation of Cement Paste
Mix 200g of cement with 0.78 times the water required for standard consistency.
Fill the Le Chatelier Mould with the cement paste, ensuring proper compaction.
Cover with glass plates and place a weight on top.
2. Initial Measurement (L₁)
After 24 hours of curing in water at 27°C ± 2°C, measure the distance between the tips of the split mould using a caliper.
3. Boiling Process
Transfer the specimen to a boiling water bath for 3 hours.
4. Final Measurement (L₂)
After cooling, measure the new distance between the tips of the mould.
5. Calculation of Expansion
Expansion=L2−L1\text{Expansion} = L_2 - L_1Expansion=L2−L1
The expansion should not exceed 10 mm for Ordinary Portland Cement (OPC).
Applications of Le Chatelier Test
✅ Quality Control of Cement – Ensures the cement does not undergo excessive expansion.
✅ Prevention of Cracks – Identifies cement with high free lime or magnesia, which can cause delayed expansion.
✅ Standard Compliance – Helps meet IS & ASTM specifications for cement manufacturing.
