A widespread misconception is prevalent that leads people to believe that creating or openings within the existing PT slabs is either incredibly difficult or impossible. A careful examination of the proper procedure proves that this is not the case.
Post-formed hole holes within PT concrete slabs differ in size, ranging from the smallest holes, which could be required to accommodate suspended services to larger holes to permit the installation of lifts and similar installations. Click here to find more details on PT concrete slabs.
In all post-tensioned slabs the most commonly used tendon layouts employ bands that provide wide space between tendons, which can be able to accommodate smaller openings. These kinds of changes tend to be simpler than other kinds of construction because the formation of holes in these spaces can be accomplished without impacting the structural integrity.
The slabs are bonded
The most popular type of post-tensioning on the market is called bonded PT. Ducts that carry high-tensile steel are composed of grout once the tendons are stretched and then locked off with the help of wedges that have been split within the anchors, which bonds the tendons to concrete.
Unbonded PT slabs
The tendons in the unbonded PT systems are anchored to the structure via end anchorages, but they are completely free to move in and out of the concrete. They are coated with grease and enclosed with plastic.
If the penetration of an unbonded slab requires tendons to be cut, they will be un-tensioned throughout their length. This is usually a requirement for lifting or restricted loading on adjacent spans during the process.