Pozzolanic materials are essentially siliceous or aluminous compounds which in themselves do not possess any Cementous property but when finally divided in the presence of water reacts with calcium hydroxide formed during hydration of cement resulting in the formation of the compound that possess cementing property. 

• It increases the workability 

• It can reduce permeability 

• Reduces water evaporation 

• Honey combing will be reduced 

• Improves cohesion that means less segregation 

• Increases the elastic modulus of concrete 

• Less heat of hydration 

• It increases the resistance of concrete to attack by salts and sulphates 

• It can reduce creep and bleeding 

• It reduces leaching in concrete

Disadvantages: 

• Curing period is more for PPC 

• Earliest strength gain is less 

• Increases shrinkage