what are these cables going to go through concrete for?

[wozzzzza]

if it was the southern states it could be heating of some sort but seeing its cairns i doubt it and not enough of it.
what are these cables weaving their way through what will be a concrete slab ? never see this before. looks like it maybe a driveway there as well or something

[DJ’s Timber]

Post Tensioning Cables

[wozzzzza]

Post Tensioning Cables

so how does that work?

[DJ’s Timber]

[wozzzzza]

ok yes, i have heard of that somewhere before, makes sense.

[ErrolFlynn]

An interesting video. I’d heard of pre-stressed but not post-stressed.

Based on the information in the video, a couple of things stood out in the photo.

a) The ducts seem too short.
b) The cables within the ducts seem only just long enough, but they appear short too, particularly if an anchor is to be fitted.
c) I presume the curved section at the end will be cut before the pour, and this is where the grout is pumped in.
d) The ducts seem very wibbly wobbly along their length. If the concrete sets and the sheath remains as it is, it occurs to me that it won't be doing its job so well.
e) I would have thought, given this is a floor, that the ducts would have been placed toward the bottom of the slab rather than the top, so that the floor can be made to bow upward, as it were, when the cables are tensioned.

[rambunctious]

if it was the southern states it could be heating of some sort but seeing its cairns i doubt it and not enough of it.
what are these cables weaving their way through what will be a concrete slab ? never see this before. looks like it maybe a driveway there as well or something

If it is a driveway then they could be same as on the roads at traffic lights, cables set into the road to sense traffic.
Knock on the site office door and ask !
I recently asked a question through the fence on a building site and was invited into the site office to view the engineers drawings.