[HN Gopher] Cylindrical aquarium housing 1,500 exotic fish burst...
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Cylindrical aquarium housing 1,500 exotic fish bursts in Berlin
Author : patrickdet
Score : 213 points
Date : 2022-12-16 10:43 UTC (12 hours ago)
(HTM) web link (www.theguardian.com)
(TXT) w3m dump (www.theguardian.com)
| artemonster wrote:
| How do they make such a huge cylinder?
| jacquesm wrote:
| Take a large sheet of acrylic, warm it, bend it by warming it
| and applying pressure. If the circumference is large take
| multiple ones. Glue ends together, glue in base plug.
| leftbit wrote:
| It's just weird learning about interesting engineering
| accomplishments by news that they're gone forever...
| bombcar wrote:
| Agreed - it would be a interesting blog to report on these kind
| of things _before_ they burst.
|
| I know of the aquariums with tubes under/through the water, but
| this seems to be something different.
| MKais wrote:
| Daily horoscope
|
| - Pisces: A difficult day despite the expansion of your living
| space
|
| - Scorpio: ...
| NoboruWataya wrote:
| This is crazy. I've been there a few times as the hotel is a
| popular spot for conferences (likely in part because of the
| attraction of the aquarium - I wonder if it will continue to be
| so popular a venue now). The aquarium was absolutely huge, I
| can't imagine what it must have been like seeing it burst.
|
| Sadly I never availed of the elevator ride through the aquarium.
| feb wrote:
| According to a german news report [1], it could be due to
| material fatigue.
|
| [1] https://www.rbb24.de/panorama/beitrag/2022/12/berlin-karl-
| li...
| weinzierl wrote:
| Yes, that is widely reported now as a very preliminary cause.
| Also that it has been completely modernized in 2020. Here is a
| promotional video of the renovation activities:
| https://vimeo.com/530397162
| usrusr wrote:
| If it's due to material fatigue it's due to engineering
| failure. That in turn may or may not be due to the yes-men
| promotion mechanism.
| PurpleRamen wrote:
| The tank was around 20 Years old. How is material fatigue an
| engineering failure at that age?
| bombcar wrote:
| If the engineers didn't know it would fail in 20 years from
| material fatigue, that's something that should be learned.
|
| They may be _blameless_ by any reasonable standard, but
| knowing how /when something will reach end of life is an
| important part of design. We learned a similar lesson with
| airplanes.
| Eduard wrote:
| > yes-men promotion mechanism
|
| huh?
| donkeyd wrote:
| People who say yes without questioning their superiors or
| clients tend to get promoted.
|
| This is what I assume they mean.
| ChuckNorris89 wrote:
| Fatigue from what? It's a stationary object housed indoors, not
| a car or plane that goes through several climatical,
| temperature and environmental changes to cause fatigue.
|
| Unless they were subjecting the tank to draining and filling
| cycles often, it seems more like a design/build fault that was
| a ticking time bomb from the start.
| jacquesm wrote:
| Thermal cycling is one option.
| Mikeb85 wrote:
| The fact an object is stationary doesn't mean forces aren't
| continuously being applied... Same goes for bridges and every
| load bearing object.
| ChuckNorris89 wrote:
| Bridges are outdoor subject to weather the forces of wind
| and the weight and harmonics of vehicles and people
| crossing them constantly.
|
| A fish tank a relatively constant by comparison.
| danwee wrote:
| Gravity.
| ChuckNorris89 wrote:
| Edited due to incorrect assumption.
| zimpenfish wrote:
| I'm no engineer but this would be static fatigue[1], no?
|
| "[S]tatic fatigue occurs during _prolonged and constant_
| application of stress " (my emphasis) - much like the
| glass/acrylic at the bottom of a 14m high, 1M litre water
| column, say.
|
| [1] https://en.wikipedia.org/wiki/Static_fatigue
| ChuckNorris89 wrote:
| Interesting I didn't know that. Thanks for sharing.
| gsatic wrote:
| The fish were having a race.
| rzzzt wrote:
| Buildings move.
| pixl97 wrote:
| This here.
|
| The earth you live on is not solid, more like a squishy
| orange. When you build a heavy building on it, the building
| can sink further.
|
| Buildings themselves are subject to the dynamic loads of
| temperature, wind, their occupants square dancing, and
| more.
|
| Sometimes unexpected loads are added. A new highway or
| building built into a rock layer near it can subject the
| previous building to vibration and other forces and cause
| damages.
| DemocracyFTW2 wrote:
| This, and it's in particular true for this very part of
| Berlin, a city that is well known for literally having
| been "built on sand", see https://de.wikipedia.org/wiki/P
| alast_der_Republik#Abriss_zwi... which is about the
| demolition of the comparatively big building of the
| Palast der Republik which was just across the street on
| the other side of the river. That building had to be
| carefully and slowly dismantled to avoid sudden changes
| in the hydrogeological (?) equilibrium of the load-
| bearing layers.
|
| Given that amateur seismic stations located 8 and 14 km
| away from the location were able to pick up a signal from
| the event[1] of a 1000 tons of water falling to the
| ground from a height of ~ 2 to 15m, one should image the
| building itself should have had some sort of influence to
| its immediate surroundings.
|
| [1] https://twitter.com/ErdbebenDE/status/160365469529326
| 3873?re...
| fwungy wrote:
| Building temperatures were mandated reduced due to energy
| sanctions. This put stress on an already sensitive structure
| and caused it to fail.
| sidlls wrote:
| 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.
| pvaldes wrote:
| 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.
| fwungy wrote:
| The hotel was required to reduce its lobby heating due to
| energy sanctions.
| pvaldes wrote:
| Hum, A graph of the aquarium water temperatures by time
| would be interesting to examine...
| philodelta wrote:
| I know people got hurt (and fish died) but all I can think is,
| this is a hotel lobby, there most certainly IS security camera
| footage of the failure and subsequent deluge and man do I want to
| know what that looked like.
| jacquesm wrote:
| There likely will not be more than a few stills worth of
| interest, this happened very quickly judging by how far out the
| street is contaminated.
| Nextgrid wrote:
| There might be legal/liability reasons why they're not
| releasing the footage immediately.
|
| Reminds me of the Champlain Towers accident - there were
| surveillance cameras everywhere, as well as a fire alarm
| control panel (that was critical to the incident as it would've
| been the one triggering an alarm to prompt everyone to
| evacuate) but no efforts were made to recover either despite
| the fire alarm panel checking in with the control centre
| several times (on battery power, over a mobile phone
| connection) _after_ the collapse, proving that it was still
| alive and recoverable.
|
| I guess they worked out that it was better to play dumb and let
| this evidence go away than recover it and potentially get into
| more trouble. I suspect it's the same situation with the
| aquarium.
| anenefan wrote:
| That's a real shame only a few fish survived. It's fortunate only
| two people hurt. That looks nasty from the picture. Maybe next
| time less brittle acrylic. Off the top of my head a 14 m high
| tower of water - there would have been approx 20 psi at the
| bottom of the tank.
| gambiting wrote:
| Just fyi - acrylic is actually less brittle than glass.
| someweirdperson wrote:
| The proper matetial to use is transparent aluminium [0]
| though.
|
| [0] https://m.youtube.com/watch?v=90eg_erObDo
| zimpenfish wrote:
| > there would have been approx 20 psi at the bottom of the
| tank.
|
| [1] agrees with you at 19.9psi
|
| [1] https://www.engineeringtoolbox.com/hydrostatic-pressure-
| wate...
| SergeAx wrote:
| I stayed at the hotel this September. My first thought was "oh,
| my, there is a breakfast area right there on a ground floor, and
| it is starts buzzing right from 6am!". Fortunately, the bang
| happened 20 mins before.
|
| Interestingly, looking at the tank from my room, I never thought
| about the scenario when it breaks. I thought "engineers must put
| a lot of extra margin when constructing this". Turned out I was
| wrong.
| peoplefromibiza wrote:
| I've been there so many times, every time I went to Berlin, sad
| news.
|
| It looked pretty cool and was a good place to bring people who
| didn't know Berlin after a visit to the beautiful Pergamonmuseum,
| which is 5 minutes walk away.
|
| But I went on the elevator only the first time, it was clear that
| that wasn't a good idea at all.
| fwungy wrote:
| 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.
| joezydeco wrote:
| Citation?
|
| You're also ignoring the thermal mass and physical pressure of
| a million liters of water.
| mikeyouse wrote:
| They're pulling that "info" from the conspiracy theorist
| website zero hedge.. that it conveniently aligns with that
| site's support of Putinist Russia should be noted. The German
| law limits public space heating to 67o which doesn't seem
| like it should be nearly enough to cause this kind of
| failure..
| joezydeco wrote:
| I would also think that 1,500 tropical fish need the water
| to be maintained at a certain temperature to keep them
| alive.
|
| If anything, the water tank was heating the room instead of
| vice versa.
| SuperFine wrote:
| How come there's no footage?
| williamscales wrote:
| I think it could take a little while to come out, but I'm sure
| they had cameras in the lobby. It did just happen this morning
| after all. The building's structural integrity is being
| checked.
| bombcar wrote:
| Exactly - the security cam footage takes a few days to be
| released _if_ the company wants it, or a few weeks to leak
| quietly if they don 't.
|
| At 6 AM you're not going to have many people standing around
| with cell phone cams for it (and anyone around when the giant
| tank starts making horrible noises would be hopefully smart
| enough to run for higher ground).
| lqet wrote:
| 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 am no expert, but if such a massive aquarium is
| only _slightly_ tilted to one side, I would expect the forces
| acting on the glass to be ill-distributed. Material fatigue would
| then only be a secondary cause.
|
| [0]
| https://www.faz.net/aktuell/gesellschaft/ungluecke/aquarium-...
| swader999 wrote:
| 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.
| jacquesm wrote:
| That's a good guess, but I'd still like to see the final
| report if and when it is published and whether or not they
| manage to find the root cause. Likely the differential made
| the problem worse to the point that something gave but I
| suspect that there is a deeper underlying cause that made it
| sensitive to that difference in temperature to begin with.
| Either a material flaw, an assembly issue or something else.
| swader999 wrote:
| I'm basing it off of what this guy is reporting. He seems
| to have an inside legit view.
| https://www.zerohedge.com/user/105370
| jacquesm wrote:
| There are some eye witness accounts about corrosion
| around the base of the tank. One way in which that could
| have caused this is because corroded metal takes up more
| space than the original and this could put point stresses
| on the acrylic. I haven't seen any engineering drawings
| (I did try to find some but there are only pretty
| pictures) so I'm not sure how much effect that would have
| but keeping the base corrosion free would seem to be an
| absolute requirement regardless of whether or not it
| would have a disastrous effect like this. So I will have
| to wait until the investigators have gone all over this,
| given the amount of money involved there is bound to be a
| very thorough investigation and after having seen a
| couple of aircraft accident investigations conclude with
| entirely different findings than the first 24 hours of
| speculation I've learned that to be patient usually pays
| off.
| swader999 wrote:
| That is fair. Security tapes might tell a lot as well.
| abduhl wrote:
| Why would you expect the forces acting on the glass to be ill-
| distributed if the enclosure were tilted slightly? Water
| pressure acts hydrostatically. The enclosure appears to have a
| circular cross section. As long as the tilt is not severe there
| is no reason to believe anything other than tensile hoop
| stresses due to equal circumferential loading will develop.
| bombcar wrote:
| I would expect it's not the tilted slightly that would matter
| but simply settling _after_ installation - a settling
| foundation can crack concrete and glass so stresses could
| change if the foundation of the tank was moving.
| a4a4a4a4 wrote:
| The normal force of the tank wall to the floor will shear
| across the acrylic if it's not perfectly flat. Pressure
| outwards is normal to the tank wall relative to the water,
| but if this force goes diagonally through the floor, that's
| bad.
| abduhl wrote:
| If the tank burst due to it shearing off of its base then
| it is not the glass that has the problem; it's the
| connection to the base. This might sound pedantic but the
| OP said the forces on the GLASS were ill-distributed. The
| most important part of after the fact disaster analysis
| from an engineering context is being excruciatingly
| specific about the performance of structural elements.
| lqet wrote:
| But isn't the overwhelming majority of the glass material
| connected to the base by the glass itself (namely the
| glass below it)?
| upsidesinclude wrote:
| If you wanted to be pedantic you would correct the
| statement because there is no glass.
|
| To be excruciatingly specific.
| abduhl wrote:
| The article refers to the aquarium as glass throughout
| it.
| kayodelycaon wrote:
| The material used is plexiglass, aka acrylic, a type of
| clear plastic. Actual glass is probably too brittle or
| expensive.
|
| People use "glass" to mean the clear part of a window,
| not the actual material, in this context.
| abduhl wrote:
| I'm glad to hear that you'd agree with me then that a
| correction saying "there is no glass" would be
| inappropriate because when someone says glass they mean
| the clear part of the tank.
| seattle_spring wrote:
| This may or may not be your intention, but fyi you are
| coming off as extremely condescending bordering on
| /r/iamverysmart level tones.
|
| I'm no expert, but I know that a hot tub on slightly
| uneven ground has a good possibility of bursting and
| ruining the tub due to how much stress the water will
| unevenly put against a side. I don't see why the same
| underlying reasons wouldn't apply here too.
| bmc7505 wrote:
| I stayed at the Radisson in 2019 for ICFP and was astounded at
| the poor quality of the building, which was undergoing
| renovations at the time. I distinctly remember noticing visible
| corrosion around the foundation of the tank structure.
| rob74 wrote:
| Considering there was a hotel lobby under the aquarium, it's
| actually a miracle that only 2 people were hurt. Too bad for the
| fish though.
|
| Also, there's a sentiment of "how could this happen, it was only
| upgraded two years ago?!" in all the articles I have read so far
| - maybe it happened _precisely because of that_? But let 's see
| what the investigation will reveal...
| tazjin wrote:
| > it's actually a miracle that only 2 people were hurt
|
| It probably helped that it happened at 6AM ...
| petodo wrote:
| even earlier, 5:30-5:45 actually reported by guests, 5:43
| fire alarm after broken front glass
|
| preliminary cause - material fatigue
| pcan77 wrote:
| as someone who has an aquarium, i'm amazed it didn't happen
| in the middle of the night. Any time I've had an overflow
| issue or something, it's always in the middle of the night
| and my water sensor is blaring
| Reason077 wrote:
| Yes, it could have been much worse if it had happened at,
| say, 6PM. Although some hotel lobbies can start to get busy
| even at that hour (airport hotels, etc).
| koheripbal wrote:
| londons_explore wrote:
| Most fishtanks have to stay in a pretty narrow range of
| temperatures or the fish die. A big professional installation
| like this I expect will have both water heating and water
| cooling (aircon, but for water).
|
| And in a glass fishtank, the glass is in good thermal contact
| with the water, but bad thermal contact with the room air -
| so the glass will end up being at fishtank temperature.
|
| So, unless they had extracted all the fish and turned the
| tank heating off, I don't think what you say is true.
| Mountain_Skies wrote:
| It's possible that the installation assumed a particular
| temperature range in the surrounding area. The water was
| still heated to the proper temperature but because the
| surrounding air was lower than design parameters allowed,
| was leaking more heat than designed for, requiring the
| water heating to work harder. Zero idea if any of that is
| correct but it shouldn't be ignored as a possibility and is
| one possibility that could be eliminated very quickly if
| not true.
| Cthulhu_ wrote:
| It's filled with tropical fish, so surely the water would
| have been at a decent temperature - definitely nowhere near
| freezing. The thing was in a fancy hotel lobby too (I was
| there once for an Apple event), I doubt they'd let the place
| go down to such low temperatures.
| throw6383878 wrote:
| There was first cold weather recently as well. November was
| VERY mild.
| hutzlibu wrote:
| And you do have first hand information, that this was the
| reason, as you speak with such authority of that matter?
|
| Like, you do know that the temperature in that hotel was
| significantly lower than last year?
|
| I mean, it seems possible, that it was the reason, (even
| though the water temperature itself hopefully did not change
| as the fishs do not like that) and the last nights were quite
| cold in germany, so stress from temperature difference is
| possible, but before I claim to know something, I wait until
| I know.
| throw827474737 wrote:
| That is one eventual first quick assumption by some (mostly
| nontechnical journalists), but nothing official and
| confirmed, or you have sources? Otherwise please don't sell
| this as fact. Knowing the place, it still had heating, so I
| personally find this also unreasonable.. would only make
| sense to me if it got to freezing temperatures or below
| 4degC, but that for sure wasn't the case.. I doubt that place
| was much colder than at other times, like maybe 2-4 degrees..
| but if you have any real details on that this would be
| welcome.
| [deleted]
| fwungy wrote:
| 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.
| krisoft wrote:
| Do you have a source on that?
| fwungy wrote:
| Too early for an official RCA, but the surrounding facts of
| the known temperature sensitivity of the aquarium, the energy
| reduction mandates in Berlin, and the unusual cold point to
| that as the most likely cause.
|
| This poster on Zerohedge provides more details:
|
| I am directly involved in the legal cleanup of this and can
| provide a little more detail as to what actually happened
| (Tyler, reach out to me you have my email if you'd like to
| verify my identity here).
|
| The city of Berlin required the hotel reduce the ambient
| temperature of the hotel lobby to save on energy due to
| sanctions. Its been abnormally cold in Berlin the past few
| nights dipping down to -11degC last night and -12degC the
| night before that. The water is heated to a constant
| temperature above 30degC for many of the fish species that
| lived in the tank.
|
| As the nights got colder and colder, the lower ambient
| temperature of the air surrounding the tank likely started
| causing deformations and hairline cracks in the bottom of the
| tank where the pressure is the greatest. Last night at -11deg
| caused the ambient temperature to drop too low given the
| reduced heating in the lobby and is what it looks like caused
| the "sudden unintentional disassembly"/catastrophic failure
| of the tank.
|
| Everyone is already lawyering up including the city, the HVAC
| manufacturer, tank manufacturer, HVAC installer, building
| engineer, hotel - the litigation is going to be fun to watch
| and work on.
|
| What isn't covered in the news is damage. The tank in 2003
| cost EUR13 million. Today its orders of magnitude more
| expensive to replace, some of the fish were quite exotic and
| are expensive losses in and of themselves. Then you have the
| damage to the hotel lobby and facade, electrical components
| of the building in the three-story basement are also effected
| and large amounts of water went into the parking garage where
| many vehicles are parked not only from the hotel and offices
| but from an attached apartment complex to the hotel.
|
| Losses are tens of millions. All because the city made the
| hotel turn down the heat.
| DemocracyFTW2 wrote:
| > All because the city made the hotel turn down the heat.
|
| That's a little bit early to start aiming at the city,
| isn't it? The call to reduce energy consumption is, if
| anything, coming on as a case of too little, too late if
| anything given the ongoing crisis over here; it is
| altogether a reasonable thing to do. As is always the case
| in Germany with such things, there will be maddening array
| of if/then/otherwise escape hatches that is part of those
| rules, and, frankly, if the management of the hotel and the
| people responsible for the aquarium had been in the know
| that keeping a constant temperature in the lobby was
| essential to the structural integrity of the aquarium and
| they still lowered it, they're mad. If they weren't told
| they can't be held responsible. If the manufacturer did
| know or should have known, they'll be in (sorry) hot water.
|
| All of this is conjecture at his point so phrases like "all
| because the city told them to turn down the heat" have to
| be understood in the conjunctive or, better, be explicitly
| written in that voice.
| plastiquebeech wrote:
| Whenever I hear people describe a complex chain of events
| only to conclude that there was a single root cause, I'm
| reminded of the old proverb:
|
| >For want of a nail the shoe was lost.
|
| >For want of a shoe the horse was lost.
|
| >For want of a horse the rider was lost.
|
| >For want of a rider the message was lost.
|
| >For want of a message the battle was lost.
|
| >For want of a battle the kingdom was lost.
|
| >And all for the want of a horseshoe nail.
|
| The moral of the proverb is: it is important to ensure
| that critical systems have redundancy built in.
| durnygbur wrote:
| 2011 - Nord Stream gas pipeline opens, 2022 - the world's
| largest acrylic aquarium in Berlin disintegrates due to the
| sanctions. What a beautiful butterfly effect... I'm afraid
| we'll see more of similar incidents in the coming months...
| Fricken wrote:
| Weird. Earlier today I awoke from a nap after strange dreams and
| attempted to produce images in midjourney of a giant aquarium
| breaking. I must psychic or something.
| passwordoops wrote:
| Shit happens with my wife All. The. Time.
|
| We're rational enough to mostly chalk it up to coincidence or
| selection bias, but not calculating enough to take advantage of
| gullible people
|
| (Edited to mention selection bias)
| namero999 wrote:
| Interesting. I'm not sure chalking up an observation is the
| rational approach. I'd be looking into the Pauli-Jung
| conjecture before doing so.
| pauletienney wrote:
| For pure curiosity, could you give us some examples of what
| happen with your wife? Thx
| passwordoops wrote:
| Case in point - yesterday morning she told me about a vivid
| dream of a major apartment fire she had. Look what just
| happened in Lyon [0].
|
| You could dream about a fire for any reason, and fires are
| unfortunately common enough to at least make local news so
| unconsciously scanning a headline during the day may plant
| a "dream worm".
|
| But this happens quite often, even for personal things,
| like details of the birth of our first kid a couple of
| weeks before the due date, down to the amount and color of
| hair, the precise time for a natural birth, and the mino
| complications right after.
|
| It always gives me split second pause because I want to
| believe ("quantum entanglement" is weird or witchery is
| real - she's East European after all). But there's almost
| always a good explanation for the percieved prescience.
|
| [0]https://www.bbc.com/news/world-europe-63997158
| Fricken wrote:
| It's Midjourney. It has me wandering the uncanny valley for
| hours every day, there is so much undiscovered country. My
| sleep is disrupted. I'm in an altered state and I'm more
| tuned to recognizing coincidences and generally making
| associations between images that may or may not be floating
| around in the latent space.
| blueflow wrote:
| You can chalk it up to selection bias, you never remember the
| predictions that were just garbage.
| pvaldes wrote:
| Again sleeping with the TV news channel turned on?
| zython wrote:
| Please dream of me winning the lottery and or becoming 10x dev.
| PainfullyNormal wrote:
| Win the lottery and become a 10x dev and maybe he'll dream
| about it.
| jacquesm wrote:
| And even before it happened. But stated afterwards.
| Traubenfuchs wrote:
| Why would you ever want to become a 10x dev instead of
| winning the lottery?
| koonsolo wrote:
| You do realise that becoming a 10x dev will mean you're
| getting underpaid? It's better to become a 0.1x developer so
| you're sure you're getting the better end of the deal ;).
| voakbasda wrote:
| Speaking as a 10x dev, this is truth. I have felt underpaid
| most of my career. After 30 years, I don't give as much at
| work anymore. I bought a farm and most of my energy goes
| there instead. I suggest wishing for a healthy balanced
| life. No happiness comes from being undervalued and
| underutilized.
| TheHappyOddish wrote:
| Wow, what a shock! I stayed here in 2017 and often looked up at
| the aquarium whilst having a coffee or beer in the foyer.
| Cthulhu_ wrote:
| I've stayed there as well for two nights a few years ago, it
| was a great attraction. Really, really large too - a million
| liters of water, five stories tall or higher, I don't even
| remember.
| jl6 wrote:
| Wow, how do you make pieces of glass that size?
| Slartie wrote:
| It was manufactured in 2004 by a US company, "International
| Concept Management": https://icm-corp.com/
|
| (side note: what a weird name for an aquarium manufacturing and
| design company)
| PurpleRamen wrote:
| Where do you have the year from? The aquarium was opened 2003
| after several years of building. And seeing it now, two weeks
| ago it even had its 19th "birthday". Speak about bad timing.
| Eduard wrote:
| According to https://www.newlift.de/details-
| referenzen/aquadom.html , several companies were involved.
| Reynolds Polymer Technology, Inc. provided the acrylic
| windows: https://www.reynoldspolymer.com/projects/aquadom/ .
|
| ICM has already removed AquaDom from their portfolio page
| https://icm-corp.com/portfolio/ , but a cached version (for
| now at least) exists at https://webcache.googleusercontent.co
| m/search?q=cache:XGSNC7... .
| durnygbur wrote:
| uuuups... they better lawyer up...
| jacquesm wrote:
| That's Germany, not the US.
| durnygbur wrote:
| yes they better lawyer up in Germany, correct
| ArchitectAnon wrote:
| 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.
| jacquesm wrote:
| Or the one that modified it, assuming that's not the one
| that originally built it.
| __alexs wrote:
| I think they are acrylic, not glass.
| MengerSponge wrote:
| Correct. https://www.bestpub.com/books/product/cid-151.html
| rjzzleep wrote:
| It looks to me as if they're actually a lot of smaller pieces
| put together, but maybe I see it incorrectly. Maybe one day,
| architects will stop designing things that are structural
| liabilities, or engineers actually get to say no to it before
| construction starts.
| ArchitectAnon wrote:
| Incredibly unlikely for any part of the structure to have
| been designed by an architect, most likely a highly
| specialist subcontractor design item. Our insurance would not
| cover it and it is illegal for architects to practice without
| insurance in many EU countries. The closest any architect
| would get to this is to go to a big fish tank company and say
| I want a big fish tank with diameter x and height y, can you
| do it and how much will it be...
| mirekrusin wrote:
| They could make it from concrete.
| imhoguy wrote:
| They should use transparent aluminium
| https://en.m.wikipedia.org/wiki/List_of_Star_Trek_materials#...
| Cthulhu_ wrote:
| "list of Star Trek materials"?
| paradoxyl wrote:
| Says a guy named "Cthulhu"? Obviously, he is being
| humorous.
| Reason077 wrote:
| 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!
| klyrs wrote:
| 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?
| 01acheru wrote:
| IMHO there should be a DE/German tag in the title.
|
| _edit: title has been edited since this comment_
| WitCanStain wrote:
| Sadly I don't read German, was anyone injured?
| beanjuice wrote:
| 2 people, 1500 fish
| whatsthatabout wrote:
| 2 people got injured and mostly all fish are dead...
| lynx23 wrote:
| Humans are horrible creatures.
| seirim wrote:
| It was an accident though, surely, and they didn't mean to
| hurt the fish.
| pvaldes wrote:
| 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?
| krisoft wrote:
| > 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?
| pvaldes wrote:
| Only two people injured after a million liter water wave was
| a miracle. Could have been much worse.
|
| But I'm probably just hypothesizing too much [again] while
| trying to analyze the case. It just feels strange coupled
| with the last long chain of strange events happening right
| now. To be fair, twenty years are a lot of time for an
| acrylic tank.
| pvaldes wrote:
| Andreas Tanschus interview:
| https://www.youtube.com/watch?v=BZXfuLEAEEs
| pvaldes wrote:
| Water pressure is very high over 60cm tall for a standard glass
| panel. This is the reason to not have really big home aquariums
| for hobbyists in the market, unless you build it directly. They
| grow in surface instead to be taller
| lqet wrote:
| Previous thread, with link to article in English:
|
| https://news.ycombinator.com/item?id=34012469
|
| Before: https://www.sueddeutsche.de/image/sz.1.5716681/1280x720
|
| After: https://www.sueddeutsche.de/image/sz.1.5716703/860x1290
|
| It seems like the inner glass (for the elevator shaft) is still
| intact.
| raydiatian wrote:
| "So long, and thanks for all the fish."
|
| -- This Aquarium, probably
| mid-kid wrote:
| Came here for this reply
| LargoLasskhyfv wrote:
| Collateral damage from the launch of Cameron's Avatar 2.
| ineil wrote:
| telesilla wrote:
| I had no idea this existed - all those visits to Berlin, wasted.
|
| Looks like it was a remarkable elevator ride.
|
| https://youtu.be/aM6niCCtOII
| wwarner wrote:
| Thanks for the video link. You can see a seam in the tank as
| the lift rises.
| G3rn0ti wrote:
| I can confirm it was a great place to visit. I went there 2018
| even as a Berlin native. The highlight of the tour was taking
| the elevator into that water dome. Impressive stuff.
|
| Too sad it's destroyed - hope insurance will cover all the
| damage. I wouldn't want to switch places with the owner
| currently...
| [deleted]
| wyuenho wrote:
| From the guidelines:
|
| > Off-Topic: Most stories about politics, or crime, or sports,
| unless they're evidence of some interesting new phenomenon.
| Videos of pratfalls or disasters, or cute animal pictures. If
| they'd cover it on TV news, it's probably off-topic.
|
| HN really needs a European mod to maintain the quality of this
| board.
| bombcar wrote:
| I mean as long as we're quoting (and breaking) the guidelines:
|
| > Please don't complain that a submission is inappropriate. If
| a story is spam or off-topic, flag it. Don't feed egregious
| comments by replying; flag them instead. If you flag, please
| don't also comment that you did.
|
| (someone flag me, I can't flag myself)
| iamben wrote:
| There's an engineering angle here that I think a lot of us
| probably find interesting?
| wyuenho wrote:
| I guarantee you car crashes has more engineering angles than
| this. There's not even a post-mortem here.
| thom wrote:
| I think large-scale engineering failures in other disciplines
| are always of interest here.
| wyuenho wrote:
| It's interesting only if there's a detailed report on the
| reasons. Otherwise this piece is news is just a "oh", instead
| of a "a-ha".
| thom wrote:
| I think we're richer for having this type of content, not
| least because someone has posted elsethread that the early
| signs point to material fatigue. The system works as far as
| I can see, and I think we're some way off the front page of
| HN being flooded by TikToks.
| krisoft wrote:
| > not least because someone has posted elsethread that
| the early signs point to material fatigue
|
| I don't mind it being posted here, but to be fair that is
| just repeating what one politician is saying: "'Of
| course, the investigation into the cause has not yet been
| completed, but the first signs point to material
| fatigue,' said Berlin Interior Senator Iris Spranger
| (SPD) of the German Press Agency."
|
| Now if someone were to point at some image and explain
| why that makes them think it was fatigue that would be
| great.
| wyuenho wrote:
| I don't know about TikTok, I just know this post was
| submitted by someone with 50 karma originally pointing to
| a German radio station news site, in German. It was only
| changed to the Guardian later, perhaps by a mod.
| nottorp wrote:
| They'll start on the report after they finish mopping 1000
| m^3 of water i guess.
|
| This is more interesting than the "look what I cloned in
| Rust" posts at the least.
| wyuenho wrote:
| What exactly have we learned that's valuable from this
| news?
| zimpenfish wrote:
| At least one person learnt of the existence of "static
| fatigue". Which I'd count as a win, personally.
| defrost wrote:
| Link to English article:
|
| https://www.theguardian.com/world/2022/dec/16/huge-cylindric...
|
| > A freestanding cylindrical aquarium housing about 1,500 exotic
| fish has burst in Berlin, causing a wave of devastation in and
| around the Sea Life tourist attraction, police have said.
|
| > Glass and other debris were swept out of the DomAquaree
| complex, which houses a Radisson hotel, a museum, shops and
| restaurants, as 1m litres of water poured out of the 14-metre-
| high tank shortly before 6am.
|
| > Operators say the aquarium has the biggest cylindrical tank in
| the world that contained 1,500 tropical fish of 80 different
| species before the incident.
|
| > The aquarium, which was last upgraded in 2020, is a big tourist
| attraction in Berlin. A 10-minute elevator ride through the tank
| was one of the highlights of the attraction.
| TeMPOraL wrote:
| > _14-metre-high tank_
|
| > _10-minute elevator ride through the tank_
|
| That's 1.4 meters per minute, or ~2.3 centimeters per second.
| The aquarium and the fish in it must have been marvelous to
| watch, because otherwise even imagining being stuck in an
| elevator moving at this pace feels terrifyingly boring to think
| about.
| Cthulhu_ wrote:
| It's a tourist attraction as part of the aquarium, not a tool
| to get from A to B; the hotel had its own regular elevator.
| slickrick216 wrote:
| Yeah it was quite nice. They'd feed the fish too and they'd
| all scramble for it.
| ceejayoz wrote:
| You've never sat on a bench for 10 minutes to look at
| something neat? They move even slower.
| Ekaros wrote:
| That is lot of water. A thousand tonnes. It could do lot worse.
| userbinator wrote:
| Imagining a 10m cube gives a good idea of the amount.
| WhackyIdeas wrote:
| Those fish must have taken a battering
| ThePadawan wrote:
| That's the UK you're thinking of, not Germany.
| jacquesm wrote:
| Any fish that got flushed out will be lost, they need things to
| be 'just so'. I once helped clean up at a friends place who had
| 30 aquariums with thousands of fish after the power went out
| longer than his UPS could provide it. The mess was sickening.
| He never had another tank after that and it was his life's
| passion.
| hardlianotion wrote:
| It feels in this case that a lot of fish were killed for no
| reason at all. I am surprised at how much this annoys me.
| liveoneggs wrote:
| With 30 tanks he was probably breeding the fish
| jacquesm wrote:
| No, just a somewhat extreme hobby.
| hardlianotion wrote:
| For avoidance of doubt, I was talking about the hotel,
| not your friend.
| TeMPOraL wrote:
| Interesting to think about. On the one hand, it's no
| different than any of the random stuff that happens to fish
| in the wild, or wildlife in general. Being killed for no
| reason at all is the _default_ in nature; humans build
| societies and civilizations and develop technologies in
| large part to avoid it.
|
| On the other hand, this feels especially sad for some
| reason.
| WhackyIdeas wrote:
| We have an industrial unit which has a mice problem.
| Every time I go to B&Q (home hardware store for non-UK
| folk) with the intention of buying mice traps, I just
| can't push the button. These mice are destroying our
| stock, but I just cannot do it. I would be a terrible
| fisherman.
| bombcar wrote:
| You can get catch-and-release mice traps, and then dump
| them in a field or on a competitor.
| WhackyIdeas wrote:
| I like this idea. Maybe I will let them breed and
| multiply first actually!
| zimpenfish wrote:
| > I would be a terrible fisherman.
|
| To be fair, you have to catch and release most fish in
| the UK which, whilst annoying for the fish, doesn't seem
| to do them much harm since there's e.g. a whole bunch of
| 30y+ old carp that keep getting caught.
|
| You're allowed to keep a certain set of game and sea fish
| if they're big enough and from the appropriate place.
| toast0 wrote:
| Have you considered outsourcing? To a cat (or cats) or a
| pest control company. The pest control company will
| probably check and close off opportunities for mice to
| enter the unit, which cats won't do, so you might want to
| consider retaining both options.
|
| Warehouse cats can be nice warehouse companions too
| (depending on what happens in the unit).
|
| I've had to do some mouse removal work in my forest
| adjacent home, and it's not pleasant, but neither is
| having mice around.
| WhackyIdeas wrote:
| We took our cat in, but she absolutely hated it. Then we
| thought she escaped for a few hours until we found her
| expertly hiding underneath some machinery.
|
| In Costco they sell this cat food called 'Maintenance
| cat'. Maybe we need one of those cats.
| toast0 wrote:
| Yeah... around here shelters separate out 'barn cats'
| from 'pet cats', barn cats are tolerant of people but not
| really socialized to appreciate people. Rather than
| taking an existing pet cat and putting him or her to
| work, I'd try adopting a barn cat and putting them to
| work. Often, barn cats do retire and become pet cats
| towards the end of their life, if circumstances allow.
|
| Of course, cats can cause a different sort of trouble
| than mice. :D
| yreg wrote:
| For how much longer than his UPS could provide it?
| jacquesm wrote:
| A couple of hours only.
| lsaferite wrote:
| I'm sorry for your friend's loss and for the lost
| livestock, but it seem like it was simply a ticking time-
| bomb.
|
| If your friend had 30 tanks and thousands of fish, they
| should have had a more involved backup plan that involved
| a dedicated generator in addition to a UPS. A small
| generator would have been a tiny fraction of the
| materials and livestock costs of running a setup like
| that.
| jacquesm wrote:
| It was the work of a lifetime. Power here has been so
| reliable that people forget that it can fail, and even
| though he was somewhat prepared it turned out not to be
| enough.
|
| Agreed though that it was a ticking time bomb. As for
| better backup plans: even autostart generators for data
| centers can fail when you need them most. Backup plans
| end up with more and more layers until you think you've
| got it all and then some little oversight will get you.
| In his case he probably could have done more but that's
| only because we're looking at it after the failure, for
| decades it worked.
| bombcar wrote:
| Most people in cities in the US have never experienced a
| power failure that lasts longer than an hour or so (and
| many places have NEVER had one). It's understandable that
| people don't think much about it.
|
| Though the moment the UPSs hit 50% you might try to run
| to Home Depot and grab a generator, but by that time
| they'd all be sold out.
| halotrope wrote:
| So Long, and Thanks for All the Fish
| durnygbur wrote:
| Now radisson will have to discount the room prices, once main
| attraction is gone...
| chasd00 wrote:
| I bet it stinks for months too
| robotnikman wrote:
| 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.
| MengerSponge wrote:
| If you're curious about the design considerations and
| construction techniques for large aquaria, the standard reference
| is Stachiw's Handbook of Acrylics for Submersibles, Hyperbaric
| Chambers, and Aquaria:
| https://www.bestpub.com/books/product/cid-151.html
|
| Plastics are weird, and examining the wreckage will give a lot of
| information about the failure mode.
| jacquesm wrote:
| A column of water that tall is nothing to mess around with.
| Even the smallest imperfection in the base materials can become
| a problem.
| MengerSponge wrote:
| 170.65 kPa, or 24.75 psi. I imagine even Flex Tape can't hold
| that!
| boppo1 wrote:
| Doesn't seem crazy, my tires hold 38 psi.
| bombcar wrote:
| PSI is a measurement that can be hard to translate
| between various items like tires and tanks and
| foundations: https://www.engineeringtoolbox.com/building-
| foundations-load...
|
| Massive tractor tires can be 50+ psi and when they pop it
| is devastating.
| jacquesm wrote:
| That can kill you. In fact even a personal car tire that
| goes can wound or kill you if you happen to be holding
| it.
| jacquesm wrote:
| And they are steel reinforced to be able to do that.
| barbegal wrote:
| 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 margins. But those
| safety margins cost hundreds of thousands of dollars for a tank
| this big so maybe they were reduced.
|
| All it takes is one incorrect application of a seam bond and a
| small crack will form. The crack may take decades to propagate
| with no way of detecting it. When the seam opens up a bit the
| crack will then propagate the entire length of the seam extremely
| rapidly and the whole tank will fail. Ideally failures would be
| slow and predictable but this is impossible with acrylic.
|
| These sorts of failures have occurred before
| https://www.plasticstoday.com/materials/when-acrylic-aquariu...
| and will keep occurring as long as this type of construction is
| used.
| IndySun wrote:
| 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?
| barbegal wrote:
| 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.
| bombcar wrote:
| Is there no way to detect cracks or is it just prohibitively
| expensive to do so?
|
| I know that metal fatigue is a known thing that airlines check
| for and when they went to carbon fiber they had to develop
| tools to detect fatigue/cracks.
| mardifoufs wrote:
| From my limited knowledge[0], it does not seem like this
| would be an easy structure to scan for inspection. Acrylic
| can even used for the wedges that interface between the
| phased array (or single element) probe [1] because it's very
| good at not interfering with ultrasounds. Water is also a
| very good "coupling" material, which makes it even harder to
| get a useful scan since there would be no "backwall"
| reflecting back the ultrasounds on the other side of the
| acrylic.
|
| There are other ways to scan for defects, but I'm mostly
| familiar with ultrasound phased arrays. Other NDT methods are
| also hard to use in the field after manufacturing.
|
| [0] I work in NDT (non destructive testing), but I'm not a
| physics engineer and (work further up the stack from the
| actual probes/scanners). So this is an approximation, and I
| might be wrong.
|
| [1] This random link is pretty useful to get an idea I think,
| but I'll also ask around our inhouse scientists if I get the
| occasion today!
|
| https://www.olympus-ims.com/en/ndt-
| tutorials/transducers/pha...
| bombcar wrote:
| So it sounds like you'd need something on both sides of the
| "glass" kind of like this aquarium magnet but much
| larger/complicated: https://www.amazon.com/JRing-Aquarium-
| Cleaner-Aquariums-Clea... and slowly move it around the
| whole tank, repeatedly scanning as it goes.
|
| So I'm going to put it in the "theoretically possible but
| nobody will do it" category for now. ;)
| jacquesm wrote:
| It's a much harder problem than that. Even if you did not
| find the crack just before taking the structure into use
| a crack could develop at any point in time after that and
| you're definitely not going to be emptying this tank on a
| regular basis for inspection.
|
| So you either detect it before commissioning or it will
| eventually fail if there is a flaw.
| jws wrote:
| Acrylic and water have virtually the same index of
| refraction, so if the crack forms on the wet side of the wall
| and wicks in water you will not detect it visually.
|
| It forms the basis of some magic tricks involving walking on
| or supporting things in water. (I say some, the rest are
| totally magic and you should enjoy them.)
| weinzierl wrote:
| I just saw a documentary (in German) from 2003 about its
| construction. There is an interview with a guy from the
| American (Colorado) company which built the tank who boasted
| that only two companies in the world could build it and the
| other one declined because they deemed it impossible. Other
| interesting facts were:
|
| - 15 segments of acrylic glass
|
| - 12 segments for the outer cylinder, 3 for the inner
|
| - all segments worth 4 million EUR
|
| - 200 wall thickness
|
| - shipped in a steel construction
|
| They did not say it, but from the video it looks like the
| segments were assembled in at the destination but not in their
| final location.
|
| EDIT: I misunderstood, looks like the outer cylinder was
| assembled in-place, the inner one on-site and then lifted
| inside.
|
| For completeness, here is the video, but it is in German:
|
| https://m.youtube.com/watch?v=E3KjGJ8AZzI
| matheusmoreira wrote:
| What's the best material for a tank like this, if not acrylic?
| Normal glass? Not educated on this subject.
| BatFastard wrote:
| Ideally it would be extruded diamond, but that technology
| will not be available until early in the 26th century. Second
| would be clear aluminum, but again that will not be available
| for another 150 years.
| gspetr wrote:
| Just one question: Why did you give my homie Stephen
| Hawking the cold shoulder when he hosted a party[0] for
| time travelers in 2009?
|
| [0] https://www.atlasobscura.com/articles/stephen-hawking-
| time-t...
| iancmceachern wrote:
| Acrylic is the best material for this application we
| currently have. If we had a better material, we would use it.
| usefulcat wrote:
| The article specifically says that this particular aquarium was
| made of glass?
| gnabgib wrote:
| The article does, but "the AquaDom was a 25-metre-tall (82
| ft) cylindrical acrylic glass aquarium"[0] Turns out that's
| just poor reporting, they could have been more specific. It
| was the largest (by volume) acrylic cylindrical aquarium in
| the world.
|
| [0]: https://en.wikipedia.org/wiki/AquaDom
| mc32 wrote:
| Also, they focus on aesthetics.
|
| They could have steel bands providing reinforcement which would
| be just slightly obtrusive at some angles, but boy, now it
| would have bands and well, it's not an uninterrupted glass
| [acrylic] cylinder.
| lqet wrote:
| Would it be possible to construct a seamless acrylic tube,
| maybe on-site?
| barbegal wrote:
| 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.
| plastiquebeech wrote:
| 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.
| barbegal wrote:
| I guess you could transport it at immense cost. But you'd
| also need a machine capable of moulding or extruding it
| this big. Current maximum for plastic pipes is about 3.5m
| diameter
| https://www.agru.at/en/applications/agruline/grand-
| opening-r... so you'd need something which is capable of
| more than 3 times the diameter.
| yencabulator wrote:
| You're making me think of this industrial scale 3D printer:
| https://www.youtube.com/watch?v=vL2KoMNzGTo
| tdeck wrote:
| That's cool but it's _all_ seams with 3d printing, so it
| seems like that would make the problem worse.
|
| By the way, here's a big cool 3D printer that prints opaque
| acrylic: https://m.youtube.com/watch?v=b3CY3P28qyQ
| robaato wrote:
| For some reason "A Fish Called Wanda" comes to mind!
|
| Or maybe that should be "Fish go Wandering"?!
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