Correct Answer - Option 2 : beams
Concept:
Prestressed concrete can be classified in the following ways depending upon design and construction:
1. Externally or internally prestressing: Externally prestressing means stress is applied externally and internally prestressing means stress is applied internally. Most of the prestressed concrete structures are internally prestressed.
2. Circular prestressing: Circular prestressing refers to prestressing in circular or round structures like tanks, pipes, etc. in which the prestressing reinforcement is wound around in a circle.
3. Linear prestressing: Linear prestressing means prestressing in linear or rectangular shaped structures such as beams, columns in which prestressing reinforcement are wound linearly i.e. along the length of structure.
4. Pre tensioning prestressing: The term pre-tensioning is used to describe any method of prestressing in which the reinforcement is stretched or tensioned before the concrete is placed.
5. Post-tensioning: Post-tensioning is a method of prestressing in which the reinforcement is tensioned after the concrete has hardened.
6. Partial or full Prestressing: When a member is designed such that under the working load there is no tensile stress in it then the concrete is said to be fully prestressed. If some tensile stresses are produced in the member under working load then it is termed as partially prestressed.
