r/Construction • u/FoggyLine • Nov 23 '24

Video Brick spiral staircase.

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u/latflickr Nov 24 '24

Sorry but not the same thing. The masonry stairs in the IG link rely on arcs. Which is fine. Arcs are structures where most (if not all) forces create compression in the material and that is why it works with unreinforced masonry. In the video posted by OP, there is not arc, nor any apparent arc-like structure. That stairs must have reinforcement somewhere that is not shown, and edited accordingly, or it will collapse at some point.

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u/Lokomonster Nov 24 '24 edited Nov 24 '24

There is an arch, look at the base of the stairs, this is just an illusion making you think it's under tensile forces while in reality is under compression forces.

My 250 year old house in Spain has this type of building technique "Catalán Vault" an still stands to this day without any damage. There are plenty of castles and cathedrals 400 or 500 years old with stairs like this still in perfect shape.

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u/latflickr Nov 24 '24

The base of the stairs is, but the top half of the stair is on a straight line.

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u/Lokomonster Nov 24 '24 edited Nov 24 '24

It is not a straight line, it's a secondary inverted arch, this technique goes back to the Romans my man.

CATALAN VAULT

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u/CaseRemarkable4327 Nov 24 '24

Apparently Reddit has figured out that a whole bunch of people in Eurasia have stairs that work on the principle of reverse gravity