Where is pre-tensioning typically performed?

• A. On the job site
• B. In a plant and the completed unit is shipped to the job site.
• C. In the field after erection
• D. In a factory that pre-tensions on site

Answer: (B)

Pre-tensioning is done in a controlled manufacturing environment where the prestressing force is applied to the tendons before the concrete cures. This setup allows precise control of tension, tendon placement, concrete quality, and curing conditions, producing a reliable, uniform member. After the unit gains strength, the prestress is transferred to the concrete, and the completed, prestressed piece is shipped to the job site for installation. Doing this on site or after erection would be far less controllable and practical, introducing more risk and variability; on-site prestressing is not the standard method for pre-tensioned members. Therefore, the typical practice is to perform pre-tensioning in a plant and ship the finished unit to the site.