What do you mean by post tensioning and pre tensioning, in PSC girders?

Question

Accepted Answer

Post tensioning and pre tensioning are methods used in prestressed concrete (PSC) girders to enhance their strength and durability.

Post tensioning involves applying tension to the concrete after it has hardened, using steel tendons or cables.
Pre tensioning involves applying tension to the tendons or cables before pouring the concrete, which transfers the force to the concrete when it hardens.
Post tensioning allows for adjustments and repairs to be made after construction, while pre tensioning provides higher strength and stiffness.
Post tensioning is commonly used in bridge construction to counteract the effects of live loads and temperature changes.
Pre tensioning is often used in the construction of precast concrete girders, where the tendons are tensioned between two anchorages before the concrete is poured.

Accepted Answer

Pre tensioning means apply the load on cables before concreting, and after concreting is called post tensioning.

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