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Comment by Animats | Hacker News Reader

Glass bottomed bridges are a thing in China, but they're being reconsidered after this.[1]

[1] https://www.mirror.co.uk/news/world-news/tourist-left-clingi...

Seems like a design flaw. You don't want the frames the glass are in to flex when the bridge flexes, so they should be isolated to a degree via the mounting hardware.

That said, I can't see how you would accomplish that and make waterproof seals between the sections, so whatever solves the bridge problem does not solve the floating pool problem.

If you're in this pool in an earthquake, aren't you fully fucked, regardless of whether the glass breaks? Getting sloshed right out of the pool, baby with the bathwater-style, seems like a distinct possibility.

London doesn't have earthquakes.

https://www.theguardian.com/science/2010/sep/16/british-scie...

(ignoring earthquakes) I guess the swimming pool would need to be on bearings and allowed some degree of rotation/translation from the buildings. This would be achievable as it does not extend that far into the building, so you should be able to have it supported in this way with a sliding bearing at the supports. I would not be surprised to see further supports and beams added to the initial architectural concept though.

I would not be surprised to see further supports and beams added to the initial architectural concept though.

Um, yes. The Golden Gate Bridge had a big stiffening retrofit in the early 1950s, with huge rectangular frames added underneath.

As for putting in bearings, the SF Bay Bridge west span was given bearings after the 1989 quake. (The east span was totally replaced.) The roadway was jacked up at each tower, and big stainless steel plates inserted so the roadway could slide relative to the tower if necessary. Plus, 17 million pounds of structural steel and half a million high-strength bolts were added, so the roadway is strong enough to slide under extreme stress without coming apart.

And that's steel, which has reasonable elasticity. Glass, not so good at that. Is it really glass, or polycarbonate? Polycarbonate has some stretch; you can bend it in a sheet metal brake and it won't crack.

From the nypost link cited:

> The structure, said to be the “largest single piece of load bearing acrylic in the world,” has been in the works for several years and was built in a Colorado factory.

I hate to link to the Daily Mail, but this article actually has plan sketches for the movements that are accommodated in the plan: https://www.dailymail.co.uk/news/article-8945619/Worlds-tran...

I wonder how they did the watertight joints that allow vertical motion.

Looks like it is. Fooled by the artist’s rendering. Again.

Anyone have a shot of the actual decking on this pool? They must have hidden expansion plates in the design to allow the bearings to work without eating human legs.

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