What is Post-Tensioning

Post tensioning is a technology for ferroconcrete project. Post-tensioning steel strand tendons, which are put inside prestressing plastic ducts, metal ducts or sleeves, are positioned in the forms before the concrete is placed. Before the service loads are applied, once the concrete has gained strength, the cables are pulled tight, or tensioned, and anchored against the outer edges of the concrete.

Post-tensioning is a kind of form of prestressing. Prestressing simply means that the steel is stressed similar as pulled or tensioned, before the concrete has to support the service loads. Most precast, prestressed concrete is actually pre-tensioned-the steel is pulled before the concrete is poured. Post-tensioned concrete means that the concrete is poured and then the tension is applied-but it is still stressed before the loads are applied so it is still prestressed.