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Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

theguardian.com

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Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#161

Post by klyrs »

Reason077 wrote: post #57
imhoguy wrote: post #19

Earlier quoted context omitted.

They should use transparent aluminium https://en.m.wikipedia.org/wiki/List_of_Star_Trek_materials#...

Modern sapphire glass (Al₂O₃) is basically transparent aluminium, and it is very strong. Probably way too expensive to make an aquarium out of it, though!

This is an amusing line of inquiry. Sapphire is growing in popularity for microchips. I found a source for single-crystal sapphire ingots... they only go up to 8 inches (~20cm) in diameter, about 60mm long. This tank was about 11 meters in diameter, 25m long. Scaling that up would be quite the project.

I mean, you could probably do chemical vapor deposition, but it wouldn't be a single crystal so what's the point?

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#162

Post by fwungy »

pvaldes wrote: post #145
sidlls wrote: post #116

Earlier quoted context omitted.

Settlement of the building it's housed in, temperature variations (things contract and expand as temperature changes), random impacts and vibrations (e.g., road traffic, heavy construction nearby), and so on. All of these contribute to fatigue.

A tropical aquarium is keep at the same temperature. Unless somebody would disconnect it to save energy or the termostat[s] would fall, shouldn't have experienced a lot of changes in their volume by this.

The hotel was required to reduce its lobby heating due to energy sanctions.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#163

Post by plastiquebeech »

barbegal wrote: post #156
lqet wrote: post #121

Earlier quoted context omitted.

Would it be possible to construct a seamless acrylic tube, maybe on-site?

Not of this size. Certainly single pieces are used in other applications where safety is even more critical such as submersibles. But manufacturing a tube this big would be impossible.

Impossible to manufacture? Or financially impossible to build a factory for the purpose and larger infrastructure to accommodate transportation?

I'm curious if there is something about acrylics which makes it impossible to make very large single pieces.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#164

Post by robotnikman »

chasd00 wrote: post #109
durnygbur wrote: post #20

Now radisson will have to discount the room prices, once main attraction is gone...

I bet it stinks for months too

I can only imagine the smell. I remember once having a small aquarium as a kid and it had that 'fishy' smell to it. The whole place must smell like that now.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#165

Post by krisoft »

fwungy wrote: post #157

The issue was caused by the forced reduction in heating due to energy sanctions. The decreased warmth of the lobby caused the aquarium, which was sensitive due to its size and construction, to contract and contort to the point of structural failure.

Do you have a source on that?

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#166

Post by ArchitectAnon »

durnygbur wrote: post #107
jacquesm wrote: post #75

Earlier quoted context omitted.

That's Germany, not the US.

yes they better lawyer up in Germany, correct

Not sure about Germany but in the UK the designers would be unlikely to still be liable anymore under the original contract to design this, liability under the contract would be up to 12 years from when the work under the contract was completed. They might be liable in tort for professional negligence but it's much harder to prove that this has occurred especially after 20 years. More likely the company that was under contract to inspect/maintain this will get hammered.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#167

Post by krisoft »

pvaldes wrote: post #141

Just to add context we could be talking easily about more than $100,000 lost only in the fishes. The materials and pumps of the aquarium should be much worse. After the strange coup try in Germany the last week, I wouldn't discard still that is not another destabilization attempt by some hypothetical agent. Weren't cameras set around the Hotel hall?

> After the strange coup try in Germany the last week, I wouldn't discard still that is not another destabilization attempt by some hypothetical agent.

How would that work? Is this site important enough to destabilize the country?

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#168

Post by swader999 »

lqet wrote: post #108

There are now many reports about material fatigue as the primary cause, but I am not so sure. Another article [0] mentioned that the building is currently analyzed by engineers because the firemen found cracks in floors and walls - they are, however, not sure if these cracks were caused by the water, or if they were already there before . In the latter case, something could be wrong with the building's foundations. I…

The hotel was told to lower their temperatures. With cold weather outside the differential between the tank and the lobby is the most likely cause.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#169

Post by joezydeco »

fwungy wrote: post #155

The root cause of this was that the hotel was forced to lower their heat due to energy sanctions. Reduced heat caused the aquarium to contract which contorted the structure, eventually causing the failure.

Citation?

You're also ignoring the thermal mass and physical pressure of a million liters of water.

Re: Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin

#170

Post by barbegal »

IndySun wrote: post #126
barbegal wrote: post #117

From an engineering perspective these sorts of acrylic tanks are a nightmare to ensure they are safe. The seams are impossible to inspect rigorously so the only real way of checking that they are safe is to load them with an excess pressure ( https://en.wikipedia.org/wiki/Hydrostatic_test ). This can't be done with a tank of this size so the engineers can only real fall back on giving the tank excessive safety margin…

Thank you barbegal. Given the height and water volume in this instance, do you consider the people involved took too huge a risk? I do believe acrylic is used in aquaparks and zoo aquatic pools. I skimmed instances of acrylic/water fails. Dare I ask, is acrylic construction a significantly cheaper option to solid alternatives?

There are no real alternatives. Glass has mostly the same bonding issues but is more expensive and heavier. Putting acrylic or glass panels in a steel frame dramatically reduces the probability of failure but you lose the wow factor of having a single sheet of transparent material.

I don't think any installation of this size can be truly safe. It has to be constructed in-situ being too large to transport so you would have to come up with some way of pressure testing the tank in-situ.

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