Question

In prestressed concrete, the primary purpose of prestressing is to ........

• A. reduce weight
• B. improve aesthetics
• C. induce tensile stress
• D. counteract tensile stress

Hint:

In prestressed concrete, prestressing is done to counteract the tensile stress developed under loading — making concrete behave more efficiently.

Answer 1

The Correct Option is D

Concrete is strong in compression but weak in tension. To enhance its performance under tensile loads, prestressing is applied. This involves inducing a pre-compression in zones of the structure that are expected to experience tension under service loads.
The main idea is: \[ \text{Prestress force} ⇒ \text{Compressive stress} ⇒ \text{Cancels tensile stress under loading} \] So, when external loads cause tensile stress, the pre-induced compressive stress neutralizes or counteracts the tension, reducing or eliminating cracks and enhancing durability.