[knarf]

Two minute very excellent animation of pre-stressed roadway

SO much is being discussed about the collapsed bridge in Florida, having worked with pre-stressed concrete, I thought it advisable to show the video orientated world just what is going on.

The principle is simple and has been used for decades.

[headstamp 2]

The first thing I thought when looking at that bridge being raised into position was where are the under girding I-beams like other non-suspension bridges/overpasses.

[volunbeer]

bfl

[Vaquero]

Sounds like they used post tensioned not pre tensioned.

[CGASMIA68]

Years ago I ustashi see these things on flat beds going down I 95 in Fl as exits were being constructed

So was this thing being put in position with a magnet went it came down or was it in place already and then collapsed.

[Real Cynic No More]

This was post-tensioned, both laterally and longitudinally. From the looks of it, the deck looked mighty thin, so the roof might have been part of the contributing structural system. There just doesn’t seem like that much concrete to take that much compression load for a 174 foot span without the roof being part of the structural system. I’m just a lowly engineer, so what do I know?

[hinckley buzzard]

Interesting. Thanks.

[redfreedom]

Very educational and interesting video. Learned much.

And here I’ve thought I was making pre-stressed structures just by having my wife around when the stuff was mixed.

[DoughtyOne]

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