Types of Concrete


Concrete is the most crucial component of buildings and infrastructure nowadays. It works brilliantly when only compressive forces (stresses) are acting, but its tensile strength is low. Its tensile strength is around 10 - 12% of its compressive strength. Its combination with reinforcement makes its most versatile material. Based on the purpose of use, there are the following types of concrete:

1. Plain Concrete: 
       It is the most straightforward type of concrete which uses cement (along with adhesive other cementitious materials are used when required), sand, water and coarse aggregate. 

It is used where no tensile stress is generated—for example - mass concreting in dams, pedestals, etc.







2. Reinforced Concrete:
This composite material has gained so much popularity because it can sustain tensile stress also. Because of reinforced concrete today, the construction of load-bearing beams and columns are possible to this extent. 
Use of reinforcement also provides warning well before the collapse because of its ductile behaviour.
 Using less steel can lead to crack propagation, and using more steel will be dangerous too. Because over reinforced member will fail in compression first, and thus the owner will not get the warning of collapse.

To provide the correct amount of reinforcement, there are some provisions in IS 456: 2000 (latest version of code).
                                     






3. Prestressed Concrete:
This type of concrete is used when the member is subjected to fatigue loading or in a case where even a hairline crack is prohibited (like pressure vessels, water tanks, etc.). 
This concrete uses prestressed steel wires embedded in it so that. While actual loading, there is no tension.














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