What is Post-Tensioning?
Post-Tensioning is a method of prestressing. Instead of stressing the reinforcing inside of large steel buttresses at a manufacturing plant, the reinforcing is simply installed on the job site after the contractor forms up the slabs or constructs the walls. The reinforcing steel is housed in a sheathing or duct that prevents the steel from bonding to the concrete so that it can be stressed after the concrete cures. Using the post-tensioning method of prestressing enables a builder to get all the advantages of prestressed concrete or masonry while still enabling the freedom to construct the member (slab, wall, column, etc,) on the job site. A typical steel strand used for post-tensioning has a tensile strength of 270,000 pounds per square inch. In comparison, a typical non-prestressed piece of reinforcing (rebar) has a tensile strength of 60,000 psi. Strands typically have a diameter of Vi in,, and are stressed to a force of 33.000 pounds using a hydraulic jack, Since April 2007. BY-CRE
