Which prestressed concrete method tensions tendons after the concrete has cured?

Which prestressed concrete method tensions tendons after the concrete has cured?

• A. Pre-tensioned
• B. Post-tensioned
• C. Combination
• D. Bonded

Answer: (B)

Tensioning after the concrete has cured is post-tensioning. In this method, ducts or channels are cast into the concrete, tendons run through them, and once the concrete reaches the required strength, a hydraulic jack pulls the tendons tight and anchors them at the ends. This creates compressive force inside the concrete, improving crack control and allowing longer spans or thinner sections. Depending on design, the tendons may be grouted to bond to the surrounding concrete (bonded) or left ungrouted (unbonded), but the defining feature is that the tensioning happens after curing. Pre-tensioning, by contrast, tightens the tendons before pouring the concrete, so the tensile force is developed while the concrete is still forming, not after it cures.

Tensioning after the concrete has cured is post-tensioning. In this method, ducts or channels are cast into the concrete, tendons run through them, and once the concrete reaches the required strength, a hydraulic jack pulls the tendons tight and anchors them at the ends. This creates compressive force inside the concrete, improving crack control and allowing longer spans or thinner sections. Depending on design, the tendons may be grouted to bond to the surrounding concrete (bonded) or left ungrouted (unbonded), but the defining feature is that the tensioning happens after curing. Pre-tensioning, by contrast, tightens the tendons before pouring the concrete, so the tensile force is developed while the concrete is still forming, not after it cures.