SULPHATE RESISTANT CEMENT- PROPERTIES,ADVANTAGES ,DISADVANTAGES AND USES

Sulphate Resistant Cement

Sulphate Resistant Cement is a type of Portland Cement in which the amount of Tricalcium aluminate (C3A) is restricted to lower than 5% and (2C 3A + C4AF) lower than 25%,which reduces the formation of sulphate salts.The reduction of sulphate salts lowers the possibility of sulphate attack on the concrete.

Properties of Sulphate Resisting Cement

Fineness - 280+ or -10 sqm/kg

Setting Time:

Initial - 80  min

Final  - 240 min

Soundness:

Lechatelier (mm) - 2     (max)

Autoclave              - 0.25 (max)

Compressive Strength:

 3 Days  - 30+ or -3

 7 Days  - 45+ or -3

28 Days - 65+ or -3

Tri calcium aluminate- 0.035

Magnesia                         - 0.02

Loss on ignition            - 0.02

Characteristics of Sulphate Resisting Cement

1.It provides maximum resistance to chloride ions,hence reduce the risk of corrosion in reinforced steel.

2.It increased workability and pumpability.

Uses of Sulphate Resisting Cement

1.It is used in foundation.

2.It is used in piling work.

3.It is used in effluent treatment plants.

4.It is used in the construction of chimney & cooling towers.

5.It is used in the construction of building near seacoast.

6.It is suitable for underground works where sulphate is present in the soil and water.

Advantages of Sulphate Resisting Cement

1.It protects the structure from the sulphate attack.

2.It has very high compressive strength.

3.Very low heat of hydration helps to avoid shrinkage cracks.

4.High durability under aggressive conditions.

5.Good for the construction of underground structure where sulphate resistant is needed much.

Disadvantages of Sulphate Resisting Cement

1.Not suitable for marine construction.

2.Not ideal for the area where their is a danger of chloride attacks.

3.Curing should be done properly with great care for min 8-10 days.

4.It is costly.