Post Tension Anchor Minimum Slab Thickness

[chamokinawan]

I have a 5" post tension slab. At the edges, where the anchorages are, it thickens up to 7" which is typical. The contractor is asking to keep it at 5" at one of the cold joints where we have a pour strip to account for shrinkage. There is no soil around the area. I have never seen 5" at the edges for the anchors and have contacted the manufacturer (left a message), but I wanted to see if anyone out there has done it. Thanks in advance.

 

[rapt]

Knowing what type of PT tendon and anchorage might make it easier to answer the question!

 

[Ingenuity]

...and is this a PT slab-on-grade, or suspended slab.

...and UNBonded or grouted system?

Thinnest unbonded PT suspended slab I have been involved with was 3-3/4" thick. It goes without saying it was a repair project!

Don't get over-influenced by the contractor's request for thinner slabs.

 

[KootK]

I'm guessing that your PT anchors would be placed concentric with the 5" slab regardless of the presence of the local thickening. As such, the anchor bearing stresses probably need to work on the 5" thickness anyhow. So I might agree to this. Bursting stresses can be checked of course.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.