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  1. Ordinary Portland cement
  2. Rapid hardening cement
  3.  High alumina cement
  4. Sulphate resisting cement
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1 Answers

Option 3 :  High alumina cement

Concept

 1 Day strength of Rapid hardening cement (RHC) = 3 Day strength of OPC with same w/c ratio

 The final setting time of RHC is < 600 min = 10 Hrs

 Whereas, the final setting time of High alumina cement (HAC) is about 5 Hours

 Compressive strength after 3 days or 72 Hrs

 The compressive strength of RHC is > 27 MPa ( IS: 8041 - 1990)

The compressive strength of HAC is > 35 MPa ( IS: 6452 - 1989 )

The following table shows various types of cement and its properties

Type of cement

Key points

Hydrophobic cement
  1. It contains 0.1-0.4% oleic acid and stearic acid
  2. Due to the presence of oleic acid, a film is formed surrounding the grains of cement, which acts as a water repellent film. Hence it has a low wetting ability.
  3. It is useful in humid places.

Rapid hardening cement
  1. Also known as high early strength cement.
  2. The curing period is less.
  3. It hardens fast but has the same setting time as OPC.
  4. It is useful in cold weather concreting.
  5. Not used for a massive concrete structure.

Quick-setting cement
  1. Quick setting cement also is known as fast setting cement or rapid set cement has less initial and final setting time.
  2. It sets quickly so the cement paste can take the required shape rapidly.
  3. It has an initial setting time of 5 minutes and a final setting time of 30 minutes

White cement
  1. The white color of cement is due to the low percentage of iron oxide.
  2. Iron oxide in white cement should be nearly 1%.
  3. Iron oxide is a coloring agent that imparts grey color to cement.

Low heat Portland cement
  1. It has a low percentage of C3S, C3A, and a high percentage of C2S.
  2. It has less heat of hydration.
  3. Useful for mass concreting.

Sulfate resisting cement
  1. It contains more amount of silicates and less amount of C3A, which results in resisting power against sulfates.
  2. Used for underwater structures, canal lining, culverts exposed to alkali action.

High alumina cement
  1. It contains about 35% alumina.
  2. It sets quickly and attains high ultimate strength in a short time.
  3. Use for structures subjected to the action of seawater, chemical plant, and furnaces.
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