What is the term for the increase in length of prestressing steel when an applied prestressing force is used?

The appropriate term for the increase in length of prestressing steel when an applied prestressing force is used is elongation. Elongation refers specifically to the increase in length due to the application of tension. In the context of prestressing, when a force is applied to the steel tendons, they are stretched, which causes them to elongate.

This concept is essential in the realms of civil and structural engineering, particularly concerning the behavior of materials under load. Understanding elongation is crucial for ensuring that structures can safely accommodate stresses without exceeding material limits or contributing to structural failure.

While tension in materials often leads to stretching, the term elongation encompasses the more precise engineering context where the increase in length is measured and analyzed under specific prestressing conditions. The other terms, such as compression and yielding, refer to different mechanical responses of materials under load and do not accurately describe the increase in length of prestressing steel.